NEWS
====

This file gives a brief overview of the major changes between each OpenSSL
release. For more details please read the CHANGES file.

OpenSSL Releases
----------------

 - [OpenSSL 3.3](#openssl-33)
 - [OpenSSL 3.2](#openssl-32)
 - [OpenSSL 3.1](#openssl-31)
 - [OpenSSL 3.0](#openssl-30)
 - [OpenSSL 1.1.1](#openssl-111)
 - [OpenSSL 1.1.0](#openssl-110)
 - [OpenSSL 1.0.2](#openssl-102)
 - [OpenSSL 1.0.1](#openssl-101)
 - [OpenSSL 1.0.0](#openssl-100)
 - [OpenSSL 0.9.x](#openssl-09x)

OpenSSL 3.3
-----------

### Major changes between OpenSSL 3.3.1 and OpenSSL 3.3.2 [3 Sep 2024]

OpenSSL 3.3.2 is a security patch release. The most severe CVE fixed in this
release is Moderate.

This release incorporates the following bug fixes and mitigations:

  * Fixed possible denial of service in X.509 name checks
    ([CVE-2024-6119])

  * Fixed possible buffer overread in SSL_select_next_proto()
    ([CVE-2024-5535])

### Major changes between OpenSSL 3.3.0 and OpenSSL 3.3.1 [4 Jun 2024]

OpenSSL 3.3.1 is a security patch release. The most severe CVE fixed in this
release is Low.

This release incorporates the following bug fixes and mitigations:

  * Fixed potential use after free after SSL_free_buffers() is called
    ([CVE-2024-4741])

  * Fixed an issue where checking excessively long DSA keys or parameters may
    be very slow
    ([CVE-2024-4603])

### Major changes between OpenSSL 3.2 and OpenSSL 3.3.0 [9 Apr 2024]

OpenSSL 3.3.0 is a feature release adding significant new functionality to
OpenSSL.

This release adds the following new features:

  * Support for qlog for tracing QUIC connections has been added

  * Added APIs to allow configuring the negotiated idle timeout for QUIC
    connections, and to allow determining the number of additional streams
    that can currently be created for a QUIC connection.

  * Added APIs to allow disabling implicit QUIC event processing for QUIC SSL
    objects

  * Added APIs to allow querying the size and utilisation of a QUIC stream's
    write buffer

  * New API `SSL_write_ex2`, which can be used to send an end-of-stream (FIN)
    condition in an optimised way when using QUIC.

  * Limited support for polling of QUIC connection and stream objects in a
    non-blocking manner.

  * Added a new EVP_DigestSqueeze() API. This allows SHAKE to squeeze multiple
    times with different output sizes.

  * Added exporter for CMake on Unix and Windows, alongside the pkg-config
    exporter.

  * The BLAKE2s hash algorithm matches BLAKE2b's support for configurable
    output length.

  * The EVP_PKEY_fromdata function has been augmented to allow for the
    derivation of CRT (Chinese Remainder Theorem) parameters when requested

  * Added API functions SSL_SESSION_get_time_ex(), SSL_SESSION_set_time_ex()
    using time_t which is Y2038 safe on 32 bit systems when 64 bit time
    is enabled

  * Unknown entries in TLS SignatureAlgorithms, ClientSignatureAlgorithms
    config options and the respective calls to SSL[_CTX]_set1_sigalgs() and
    SSL[_CTX]_set1_client_sigalgs() that start with `?` character are
    ignored and the configuration will still be used.

  * Added `-set_issuer` and `-set_subject` options to `openssl x509` to
    override the Issuer and Subject when creating a certificate. The `-subj`
    option now is an alias for `-set_subject`.

  * Added several new features of CMPv3 defined in RFC 9480 and RFC 9483

  * New option `SSL_OP_PREFER_NO_DHE_KEX`, which allows configuring a TLS1.3
    server to prefer session resumption using PSK-only key exchange over PSK
    with DHE, if both are available.

  * New atexit configuration switch, which controls whether the OPENSSL_cleanup
    is registered when libcrypto is unloaded.

  * Added X509_STORE_get1_objects to avoid issues with the existing
    X509_STORE_get0_objects API in multi-threaded applications.

This release incorporates the following potentially significant or incompatible
changes:

  * Applied AES-GCM unroll8 optimisation to Microsoft Azure Cobalt 100

  * Optimized AES-CTR for ARM Neoverse V1 and V2

  * Enable AES and SHA3 optimisations on Applie Silicon M3-based MacOS systems
    similar to M1/M2.

  * Various optimizations for cryptographic routines using RISC-V vector crypto
    extensions

  * Added assembly implementation for md5 on loongarch64

  * Accept longer context for TLS 1.2 exporters

  * The activate and soft_load configuration settings for providers in
    openssl.cnf have been updated to require a value of [1|yes|true|on]
    (in lower or UPPER case) to enable the setting. Conversely a value
    of [0|no|false|off] will disable the setting.

  * In `openssl speed`, changed the default hash function used with `hmac` from
    `md5` to `sha256`.

  * The `-verify` option to the `openssl crl` and `openssl req` will make the
    program exit with 1 on failure.

  * The d2i_ASN1_GENERALIZEDTIME(), d2i_ASN1_UTCTIME(), ASN1_TIME_check(), and
    related functions have been augmented to check for a minimum length of
    the input string, in accordance with ITU-T X.690 section 11.7 and 11.8.

  * OPENSSL_sk_push() and sk_<TYPE>_push() functions now return 0 instead of -1
    if called with a NULL stack argument.

  * New limit on HTTP response headers is introduced to HTTP client. The
    default limit is set to 256 header lines.

This release incorporates the following bug fixes and mitigations:

  * The BIO_get_new_index() function can only be called 127 times before it
    reaches its upper bound of BIO_TYPE_MASK and will now return -1 once its
    exhausted.

A more detailed list of changes in this release can be found in the
[CHANGES.md] file.

Users interested in using the new QUIC functionality are encouraged to read the
[README file for QUIC][README-QUIC.md], which provides links to relevant
documentation and example code.

As always, bug reports and issues relating to OpenSSL can be [filed on our issue
tracker][issue tracker].

OpenSSL 3.2
-----------

### Major changes between OpenSSL 3.2.1 and OpenSSL 3.2.2 [under development]

OpenSSL 3.2.2 is a security patch release. The most severe CVE fixed in this
release is Low.

This release incorporates the following bug fixes and mitigations:

  * Fixed unbounded memory growth with session handling in TLSv1.3
    ([CVE-2024-2511])

### Major changes between OpenSSL 3.2.0 and OpenSSL 3.2.1 [30 Jan 2024]

OpenSSL 3.2.1 is a security patch release. The most severe CVE fixed in this
release is Low.

This release incorporates the following bug fixes and mitigations:

  * Fixed PKCS12 Decoding crashes
    ([CVE-2024-0727])

  * Fixed excessive time spent checking invalid RSA public keys
    ([CVE-2023-6237])

  * Fixed POLY1305 MAC implementation corrupting vector registers on PowerPC
    CPUs which support PowerISA 2.07
    ([CVE-2023-6129])

### Major changes between OpenSSL 3.1 and OpenSSL 3.2.0 [23 Nov 2023]

OpenSSL 3.2.0 is a feature release adding significant new functionality to
OpenSSL.

This release incorporates the following potentially significant or incompatible
changes:

  * The default SSL/TLS security level has been changed from 1 to 2.

  * The `x509`, `ca`, and `req` apps now always produce X.509v3 certificates.

  * Subject or issuer names in X.509 objects are now displayed as UTF-8 strings
    by default. Also spaces surrounding `=` in DN output are removed.

This release adds the following new features:

  * Support for client side QUIC, including support for
    multiple streams (RFC 9000)

  * Support for Ed25519ctx, Ed25519ph and Ed448ph in addition
    to existing support for Ed25519 and Ed448 (RFC 8032)

  * Support for deterministic ECDSA signatures (RFC 6979)

  * Support for AES-GCM-SIV, a nonce-misuse-resistant AEAD (RFC 8452)

  * Support for the Argon2 KDF, along with supporting thread pool
    functionality (RFC 9106)

  * Support for Hybrid Public Key Encryption (HPKE) (RFC 9180)

  * Support for SM4-XTS

  * Support for Brainpool curves in TLS 1.3

  * Support for TLS Raw Public Keys (RFC 7250)

  * Support for TCP Fast Open on Linux, macOS and FreeBSD,
    where enabled and supported (RFC 7413)

  * Support for TLS certificate compression, including library
    support for zlib, Brotli and zstd (RFC 8879)

  * Support for provider-based pluggable signature algorithms
    in TLS 1.3 with supporting CMS and X.509 functionality

    With a suitable provider this enables the use of post-quantum/quantum-safe
    cryptography.

  * Support for using the Windows system certificate store as a source of
    trusted root certificates

    This is not yet enabled by default and must be activated using an
    environment variable. This is likely to become enabled by default
    in a future feature release.

  * Support for using the IANA standard names in TLS ciphersuite configuration

  * Multiple new features and improvements to CMP protocol support

The following known issues are present in this release and will be rectified
in a future release:

  * Provider-based signature algorithms cannot be configured using the
    SignatureAlgorithms configuration file parameter (#22761)

This release incorporates the following documentation enhancements:

  * Added multiple tutorials on the OpenSSL library and in particular
    on writing various clients (using TLS and QUIC protocols) with libssl

    See [OpenSSL Guide].

This release incorporates the following bug fixes and mitigations:

  * Fixed excessive time spent in DH check / generation with large Q parameter
    value
    ([CVE-2023-5678])

A more detailed list of changes in this release can be found in the
[CHANGES.md] file.

Users interested in using the new QUIC functionality are encouraged to read the
[README file for QUIC][README-QUIC.md], which provides links to relevant
documentation and example code.

As always, bug reports and issues relating to OpenSSL can be [filed on our issue
tracker][issue tracker].

OpenSSL 3.1
-----------

### Major changes between OpenSSL 3.1.3 and OpenSSL 3.1.4 [24 Oct 2023]

  * Mitigate incorrect resize handling for symmetric cipher keys and IVs.
    ([CVE-2023-5363])

### Major changes between OpenSSL 3.1.2 and OpenSSL 3.1.3 [19 Sep 2023]

  * Fix POLY1305 MAC implementation corrupting XMM registers on Windows
    ([CVE-2023-4807])

### Major changes between OpenSSL 3.1.1 and OpenSSL 3.1.2 [1 Aug 2023]

  * Fix excessive time spent checking DH q parameter value ([CVE-2023-3817])
  * Fix DH_check() excessive time with over sized modulus ([CVE-2023-3446])
  * Do not ignore empty associated data entries with AES-SIV ([CVE-2023-2975])
  * When building with the `enable-fips` option and using the resulting
    FIPS provider, TLS 1.2 will, by default, mandate the use of an
    extended master secret and the Hash and HMAC DRBGs will not operate
    with truncated digests.

### Major changes between OpenSSL 3.1.0 and OpenSSL 3.1.1 [30 May 2023]

  * Mitigate for very slow `OBJ_obj2txt()` performance with gigantic OBJECT
    IDENTIFIER sub-identities.  ([CVE-2023-2650])
  * Fixed buffer overread in AES-XTS decryption on ARM 64 bit platforms
    ([CVE-2023-1255])
  * Fixed documentation of X509_VERIFY_PARAM_add0_policy() ([CVE-2023-0466])
  * Fixed handling of invalid certificate policies in leaf certificates
    ([CVE-2023-0465])
  * Limited the number of nodes created in a policy tree ([CVE-2023-0464])

### Major changes between OpenSSL 3.0 and OpenSSL 3.1.0 [14 Mar 2023]

  * SSL 3, TLS 1.0, TLS 1.1, and DTLS 1.0 only work at security level 0.
  * Performance enhancements and new platform support including new
    assembler code algorithm implementations.
  * Deprecated LHASH statistics functions.
  * FIPS 140-3 compliance changes.

OpenSSL 3.0
-----------

### Major changes between OpenSSL 3.0.7 and OpenSSL 3.0.8 [7 Feb 2023]

  * Fixed NULL dereference during PKCS7 data verification ([CVE-2023-0401])
  * Fixed X.400 address type confusion in X.509 GeneralName ([CVE-2023-0286])
  * Fixed NULL dereference validating DSA public key ([CVE-2023-0217])
  * Fixed Invalid pointer dereference in d2i_PKCS7 functions ([CVE-2023-0216])
  * Fixed Use-after-free following BIO_new_NDEF ([CVE-2023-0215])
  * Fixed Double free after calling PEM_read_bio_ex ([CVE-2022-4450])
  * Fixed Timing Oracle in RSA Decryption ([CVE-2022-4304])
  * Fixed X.509 Name Constraints Read Buffer Overflow ([CVE-2022-4203])
  * Fixed X.509 Policy Constraints Double Locking ([CVE-2022-3996])

### Major changes between OpenSSL 3.0.6 and OpenSSL 3.0.7 [1 Nov 2022]

  * Added RIPEMD160 to the default provider.
  * Fixed regressions introduced in 3.0.6 version.
  * Fixed two buffer overflows in punycode decoding functions.
    ([CVE-2022-3786]) and ([CVE-2022-3602])

### Major changes between OpenSSL 3.0.5 and OpenSSL 3.0.6 [11 Oct 2022]

  * Fix for custom ciphers to prevent accidental use of NULL encryption
    ([CVE-2022-3358])

### Major changes between OpenSSL 3.0.4 and OpenSSL 3.0.5 [5 Jul 2022]

  * Fixed heap memory corruption with RSA private key operation
    ([CVE-2022-2274])
  * Fixed AES OCB failure to encrypt some bytes on 32-bit x86 platforms
    ([CVE-2022-2097])

### Major changes between OpenSSL 3.0.3 and OpenSSL 3.0.4 [21 Jun 2022]

  * Fixed additional bugs in the c_rehash script which was not properly
    sanitising shell metacharacters to prevent command injection
    ([CVE-2022-2068])

### Major changes between OpenSSL 3.0.2 and OpenSSL 3.0.3 [3 May 2022]

  * Fixed a bug in the c_rehash script which was not properly sanitising shell
    metacharacters to prevent command injection ([CVE-2022-1292])
  * Fixed a bug in the function `OCSP_basic_verify` that verifies the signer
    certificate on an OCSP response ([CVE-2022-1343])
  * Fixed a bug where the RC4-MD5 ciphersuite incorrectly used the
    AAD data as the MAC key ([CVE-2022-1434])
  * Fix a bug in the OPENSSL_LH_flush() function that breaks reuse of the memory
    occupied by the removed hash table entries ([CVE-2022-1473])

### Major changes between OpenSSL 3.0.1 and OpenSSL 3.0.2 [15 Mar 2022]

  * Fixed a bug in the BN_mod_sqrt() function that can cause it to loop forever
    for non-prime moduli ([CVE-2022-0778])

### Major changes between OpenSSL 3.0.0 and OpenSSL 3.0.1 [14 Dec 2021]

  * Fixed invalid handling of X509_verify_cert() internal errors in libssl
    ([CVE-2021-4044])
  * Allow fetching an operation from the provider that owns an unexportable key
    as a fallback if that is still allowed by the property query.

### Major changes between OpenSSL 1.1.1 and OpenSSL 3.0.0 [7 sep 2021]

  * Enhanced 'openssl list' with many new options.
  * Added migration guide to man7.
  * Implemented support for fully "pluggable" TLSv1.3 groups.
  * Added support for Kernel TLS (KTLS).
  * Changed the license to the Apache License v2.0.
  * Moved all variations of the EVP ciphers CAST5, BF, IDEA, SEED, RC2,
    RC4, RC5, and DES to the legacy provider.
  * Moved the EVP digests MD2, MD4, MDC2, WHIRLPOOL and RIPEMD-160 to the legacy
    provider.
  * Added convenience functions for generating asymmetric key pairs.
  * Deprecated the `OCSP_REQ_CTX` type and functions.
  * Deprecated the `EC_KEY` and `EC_KEY_METHOD` types and functions.
  * Deprecated the `RSA` and `RSA_METHOD` types and functions.
  * Deprecated the `DSA` and `DSA_METHOD` types and functions.
  * Deprecated the `DH` and `DH_METHOD` types and functions.
  * Deprecated the `ERR_load_` functions.
  * Remove the `RAND_DRBG` API.
  * Deprecated the `ENGINE` API.
  * Added `OSSL_LIB_CTX`, a libcrypto library context.
  * Added various `_ex` functions to the OpenSSL API that support using
    a non-default `OSSL_LIB_CTX`.
  * Interactive mode is removed from the 'openssl' program.
  * The X25519, X448, Ed25519, Ed448, SHAKE128 and SHAKE256 algorithms are
    included in the FIPS provider.
  * X509 certificates signed using SHA1 are no longer allowed at security
    level 1 or higher. The default security level for TLS is 1, so
    certificates signed using SHA1 are by default no longer trusted to
    authenticate servers or clients.
  * enable-crypto-mdebug and enable-crypto-mdebug-backtrace were mostly
    disabled; the project uses address sanitize/leak-detect instead.
  * Added a Certificate Management Protocol (CMP, RFC 4210) implementation
    also covering CRMF (RFC 4211) and HTTP transfer (RFC 6712).
    It is part of the crypto lib and adds a 'cmp' app with a demo configuration.
    All widely used CMP features are supported for both clients and servers.
  * Added a proper HTTP client supporting GET with optional redirection, POST,
    arbitrary request and response content types, TLS, persistent connections,
    connections via HTTP(s) proxies, connections and exchange via user-defined
    BIOs (allowing implicit connections), and timeout checks.
  * Added util/check-format.pl for checking adherence to the coding guidelines.
  * Added OSSL_ENCODER, a generic encoder API.
  * Added OSSL_DECODER, a generic decoder API.
  * Added OSSL_PARAM_BLD, an easier to use API to OSSL_PARAM.
  * Added error raising macros, ERR_raise() and ERR_raise_data().
  * Deprecated ERR_put_error(), ERR_get_error_line(), ERR_get_error_line_data(),
    ERR_peek_error_line_data(), ERR_peek_last_error_line_data() and
    ERR_func_error_string().
  * Added OSSL_PROVIDER_available(), to check provider availability.
  * Added 'openssl mac' that uses the EVP_MAC API.
  * Added 'openssl kdf' that uses the EVP_KDF API.
  * Add OPENSSL_info() and 'openssl info' to get built-in data.
  * Add support for enabling instrumentation through trace and debug
    output.
  * Changed our version number scheme and set the next major release to
    3.0.0
  * Added EVP_MAC, an EVP layer MAC API, and a generic EVP_PKEY to EVP_MAC
    bridge.  Supported MACs are: BLAKE2, CMAC, GMAC, HMAC, KMAC, POLY1305
    and SIPHASH.
  * Removed the heartbeat message in DTLS feature.
  * Added EVP_KDF, an EVP layer KDF and PRF API, and a generic EVP_PKEY to
    EVP_KDF bridge.  Supported KDFs are: HKDF, KBKDF, KRB5 KDF, PBKDF2,
    PKCS12 KDF, SCRYPT, SSH KDF, SSKDF, TLS1 PRF, X9.42 KDF and X9.63 KDF.
  * All of the low-level MD2, MD4, MD5, MDC2, RIPEMD160, SHA1, SHA224,
    SHA256, SHA384, SHA512 and Whirlpool digest functions have been
    deprecated.
  * All of the low-level AES, Blowfish, Camellia, CAST, DES, IDEA, RC2,
    RC4, RC5 and SEED cipher functions have been deprecated.
  * All of the low-level DH, DSA, ECDH, ECDSA and RSA public key functions
    have been deprecated.
  * SSL 3, TLS 1.0, TLS 1.1, and DTLS 1.0 only work at security level 0,
    except when RSA key exchange without SHA1 is used.
  * Added providers, a new pluggability concept that will replace the
    ENGINE API and ENGINE implementations.

OpenSSL 1.1.1
-------------

### Major changes between OpenSSL 1.1.1k and OpenSSL 1.1.1l [24 Aug 2021]

  * Fixed an SM2 Decryption Buffer Overflow ([CVE-2021-3711])
  * Fixed various read buffer overruns processing ASN.1 strings ([CVE-2021-3712])

### Major changes between OpenSSL 1.1.1j and OpenSSL 1.1.1k [25 Mar 2021]

  * Fixed a problem with verifying a certificate chain when using the
    X509_V_FLAG_X509_STRICT flag ([CVE-2021-3450])
  * Fixed an issue where an OpenSSL TLS server may crash if sent a maliciously
    crafted renegotiation ClientHello message from a client ([CVE-2021-3449])

### Major changes between OpenSSL 1.1.1i and OpenSSL 1.1.1j [16 Feb 2021]

  * Fixed a NULL pointer deref in the X509_issuer_and_serial_hash()
    function ([CVE-2021-23841])
  * Fixed the RSA_padding_check_SSLv23() function and the RSA_SSLV23_PADDING
    padding mode to correctly check for rollback attacks
  * Fixed an overflow in the EVP_CipherUpdate, EVP_EncryptUpdate and
    EVP_DecryptUpdate functions ([CVE-2021-23840])
  * Fixed SRP_Calc_client_key so that it runs in constant time

### Major changes between OpenSSL 1.1.1h and OpenSSL 1.1.1i [8 Dec 2020]

  * Fixed NULL pointer deref in GENERAL_NAME_cmp ([CVE-2020-1971])

### Major changes between OpenSSL 1.1.1g and OpenSSL 1.1.1h [22 Sep 2020]

  * Disallow explicit curve parameters in verifications chains when
    X509_V_FLAG_X509_STRICT is used
  * Enable 'MinProtocol' and 'MaxProtocol' to configure both TLS and DTLS
    contexts
  * Oracle Developer Studio will start reporting deprecation warnings

### Major changes between OpenSSL 1.1.1f and OpenSSL 1.1.1g [21 Apr 2020]

  * Fixed segmentation fault in SSL_check_chain() ([CVE-2020-1967])

### Major changes between OpenSSL 1.1.1e and OpenSSL 1.1.1f [31 Mar 2020]

  * Revert the unexpected EOF reporting via SSL_ERROR_SSL

### Major changes between OpenSSL 1.1.1d and OpenSSL 1.1.1e [17 Mar 2020]

  * Fixed an overflow bug in the x64_64 Montgomery squaring procedure
    used in exponentiation with 512-bit moduli ([CVE-2019-1551])

### Major changes between OpenSSL 1.1.1c and OpenSSL 1.1.1d [10 Sep 2019]

  * Fixed a fork protection issue ([CVE-2019-1549])
  * Fixed a padding oracle in PKCS7_dataDecode and CMS_decrypt_set1_pkey
    ([CVE-2019-1563])
  * For built-in EC curves, ensure an EC_GROUP built from the curve name is
    used even when parsing explicit parameters
  * Compute ECC cofactors if not provided during EC_GROUP construction
    ([CVE-2019-1547])
  * Early start up entropy quality from the DEVRANDOM seed source has been
    improved for older Linux systems
  * Correct the extended master secret constant on EBCDIC systems
  * Use Windows installation paths in the mingw builds ([CVE-2019-1552])
  * Changed DH_check to accept parameters with order q and 2q subgroups
  * Significantly reduce secure memory usage by the randomness pools
  * Revert the DEVRANDOM_WAIT feature for Linux systems

### Major changes between OpenSSL 1.1.1b and OpenSSL 1.1.1c [28 May 2019]

  * Prevent over long nonces in ChaCha20-Poly1305 ([CVE-2019-1543])

### Major changes between OpenSSL 1.1.1a and OpenSSL 1.1.1b [26 Feb 2019]

  * Change the info callback signals for the start and end of a post-handshake
    message exchange in TLSv1.3.
  * Fix a bug in DTLS over SCTP. This breaks interoperability with older
    versions of OpenSSL like OpenSSL 1.1.0 and OpenSSL 1.0.2.

### Major changes between OpenSSL 1.1.1 and OpenSSL 1.1.1a [20 Nov 2018]

  * Timing vulnerability in DSA signature generation ([CVE-2018-0734])
  * Timing vulnerability in ECDSA signature generation ([CVE-2018-0735])

### Major changes between OpenSSL 1.1.0i and OpenSSL 1.1.1 [11 Sep 2018]

  * Support for TLSv1.3 added. The TLSv1.3 implementation includes:
    * Fully compliant implementation of RFC8446 (TLSv1.3) on by default
    * Early data (0-RTT)
    * Post-handshake authentication and key update
    * Middlebox Compatibility Mode
    * TLSv1.3 PSKs
    * Support for all five RFC8446 ciphersuites
    * RSA-PSS signature algorithms (backported to TLSv1.2)
    * Configurable session ticket support
    * Stateless server support
    * Rewrite of the packet construction code for "safer" packet handling
    * Rewrite of the extension handling code
    For further important information, see the [TLS1.3 page](
    https://wiki.openssl.org/index.php/TLS1.3) in the OpenSSL Wiki.

  * Complete rewrite of the OpenSSL random number generator to introduce the
    following capabilities
      * The default RAND method now utilizes an AES-CTR DRBG according to
        NIST standard SP 800-90Ar1.
      * Support for multiple DRBG instances with seed chaining.
      * There is a public and private DRBG instance.
      * The DRBG instances are fork-safe.
      * Keep all global DRBG instances on the secure heap if it is enabled.
      * The public and private DRBG instance are per thread for lock free
      operation
  * Support for various new cryptographic algorithms including:
      * SHA3
      * SHA512/224 and SHA512/256
      * EdDSA (both Ed25519 and Ed448) including X509 and TLS support
      * X448 (adding to the existing X25519 support in 1.1.0)
      * Multi-prime RSA
      * SM2
      * SM3
      * SM4
      * SipHash
      * ARIA (including TLS support)
  * Significant Side-Channel attack security improvements
  * Add a new ClientHello callback to provide the ability to adjust the SSL
  object at an early stage.
  * Add 'Maximum Fragment Length' TLS extension negotiation and support
  * A new STORE module, which implements a uniform and URI based reader of
   stores that can contain keys, certificates, CRLs and numerous other
  objects.
  * Move the display of configuration data to configdata.pm.
  * Allow GNU style "make variables" to be used with Configure.
  * Claim the namespaces OSSL and OPENSSL, represented as symbol prefixes
  * Rewrite of devcrypto engine

OpenSSL 1.1.0
-------------

### Major changes between OpenSSL 1.1.0k and OpenSSL 1.1.0l [10 Sep 2019]

  * Fixed a padding oracle in PKCS7_dataDecode and CMS_decrypt_set1_pkey
    ([CVE-2019-1563])
  * For built-in EC curves, ensure an EC_GROUP built from the curve name is
    used even when parsing explicit parameters
  * Compute ECC cofactors if not provided during EC_GROUP construction
    ([CVE-2019-1547])
  * Use Windows installation paths in the mingw builds ([CVE-2019-1552])

### Major changes between OpenSSL 1.1.0j and OpenSSL 1.1.0k [28 May 2019]

  * Prevent over long nonces in ChaCha20-Poly1305 ([CVE-2019-1543])

### Major changes between OpenSSL 1.1.0i and OpenSSL 1.1.0j [20 Nov 2018]

  * Timing vulnerability in DSA signature generation ([CVE-2018-0734])
  * Timing vulnerability in ECDSA signature generation ([CVE-2018-0735])

### Major changes between OpenSSL 1.1.0h and OpenSSL 1.1.0i [14 Aug 2018]

  * Client DoS due to large DH parameter ([CVE-2018-0732])
  * Cache timing vulnerability in RSA Key Generation ([CVE-2018-0737])

### Major changes between OpenSSL 1.1.0g and OpenSSL 1.1.0h [27 Mar 2018]

  * Constructed ASN.1 types with a recursive definition could exceed the
    stack ([CVE-2018-0739])
  * Incorrect CRYPTO_memcmp on HP-UX PA-RISC ([CVE-2018-0733])
  * rsaz_1024_mul_avx2 overflow bug on x86_64 ([CVE-2017-3738])

### Major changes between OpenSSL 1.1.0f and OpenSSL 1.1.0g [2 Nov 2017]

  * bn_sqrx8x_internal carry bug on x86_64 ([CVE-2017-3736])
  * Malformed X.509 IPAddressFamily could cause OOB read ([CVE-2017-3735])

### Major changes between OpenSSL 1.1.0e and OpenSSL 1.1.0f [25 May 2017]

  * config now recognises 64-bit mingw and chooses mingw64 instead of mingw

### Major changes between OpenSSL 1.1.0d and OpenSSL 1.1.0e [16 Feb 2017]

  * Encrypt-Then-Mac renegotiation crash ([CVE-2017-3733])

### Major changes between OpenSSL 1.1.0c and OpenSSL 1.1.0d [26 Jan 2017]

  * Truncated packet could crash via OOB read ([CVE-2017-3731])
  * Bad (EC)DHE parameters cause a client crash ([CVE-2017-3730])
  * BN_mod_exp may produce incorrect results on x86_64 ([CVE-2017-3732])

### Major changes between OpenSSL 1.1.0b and OpenSSL 1.1.0c [10 Nov 2016]

  * ChaCha20/Poly1305 heap-buffer-overflow ([CVE-2016-7054])
  * CMS Null dereference ([CVE-2016-7053])
  * Montgomery multiplication may produce incorrect results ([CVE-2016-7055])

### Major changes between OpenSSL 1.1.0a and OpenSSL 1.1.0b [26 Sep 2016]

  * Fix Use After Free for large message sizes ([CVE-2016-6309])

### Major changes between OpenSSL 1.1.0 and OpenSSL 1.1.0a [22 Sep 2016]

  * OCSP Status Request extension unbounded memory growth ([CVE-2016-6304])
  * SSL_peek() hang on empty record ([CVE-2016-6305])
  * Excessive allocation of memory in tls_get_message_header()
    ([CVE-2016-6307])
  * Excessive allocation of memory in dtls1_preprocess_fragment()
    ([CVE-2016-6308])

### Major changes between OpenSSL 1.0.2h and OpenSSL 1.1.0 [25 Aug 2016]

  * Copyright text was shrunk to a boilerplate that points to the license
  * "shared" builds are now the default when possible
  * Added support for "pipelining"
  * Added the AFALG engine
  * New threading API implemented
  * Support for ChaCha20 and Poly1305 added to libcrypto and libssl
  * Support for extended master secret
  * CCM ciphersuites
  * Reworked test suite, now based on perl, Test::Harness and Test::More
  * *Most* libcrypto and libssl public structures were made opaque,
    including:
    BIGNUM and associated types, EC_KEY and EC_KEY_METHOD,
    DH and DH_METHOD, DSA and DSA_METHOD, RSA and RSA_METHOD,
    BIO and BIO_METHOD, EVP_MD_CTX, EVP_MD, EVP_CIPHER_CTX,
    EVP_CIPHER, EVP_PKEY and associated types, HMAC_CTX,
    X509, X509_CRL, X509_OBJECT, X509_STORE_CTX, X509_STORE,
    X509_LOOKUP, X509_LOOKUP_METHOD
  * libssl internal structures made opaque
  * SSLv2 support removed
  * Kerberos ciphersuite support removed
  * RC4 removed from DEFAULT ciphersuites in libssl
  * 40 and 56 bit cipher support removed from libssl
  * All public header files moved to include/openssl, no more symlinking
  * SSL/TLS state machine, version negotiation and record layer rewritten
  * EC revision: now operations use new EC_KEY_METHOD.
  * Support for OCB mode added to libcrypto
  * Support for asynchronous crypto operations added to libcrypto and libssl
  * Deprecated interfaces can now be disabled at build time either
    relative to the latest release via the "no-deprecated" Configure
    argument, or via the "--api=1.1.0|1.0.0|0.9.8" option.
  * Application software can be compiled with -DOPENSSL_API_COMPAT=version
    to ensure that features deprecated in that version are not exposed.
  * Support for RFC6698/RFC7671 DANE TLSA peer authentication
  * Change of Configure to use --prefix as the main installation
    directory location rather than --openssldir.  The latter becomes
    the directory for certs, private key and openssl.cnf exclusively.
  * Reworked BIO networking library, with full support for IPv6.
  * New "unified" build system
  * New security levels
  * Support for scrypt algorithm
  * Support for X25519
  * Extended SSL_CONF support using configuration files
  * KDF algorithm support. Implement TLS PRF as a KDF.
  * Support for Certificate Transparency
  * HKDF support.

OpenSSL 1.0.2
-------------

### Major changes between OpenSSL 1.0.2s and OpenSSL 1.0.2t [10 Sep 2019]

  * Fixed a padding oracle in PKCS7_dataDecode and CMS_decrypt_set1_pkey
    ([CVE-2019-1563])
  * For built-in EC curves, ensure an EC_GROUP built from the curve name is
    used even when parsing explicit parameters
  * Compute ECC cofactors if not provided during EC_GROUP construction
    ([CVE-2019-1547])
  * Document issue with installation paths in diverse Windows builds
    ([CVE-2019-1552])

### Major changes between OpenSSL 1.0.2r and OpenSSL 1.0.2s [28 May 2019]

  * None

### Major changes between OpenSSL 1.0.2q and OpenSSL 1.0.2r [26 Feb 2019]

  * 0-byte record padding oracle ([CVE-2019-1559])

### Major changes between OpenSSL 1.0.2p and OpenSSL 1.0.2q [20 Nov 2018]

  * Microarchitecture timing vulnerability in ECC scalar multiplication ([CVE-2018-5407])
  * Timing vulnerability in DSA signature generation ([CVE-2018-0734])

### Major changes between OpenSSL 1.0.2o and OpenSSL 1.0.2p [14 Aug 2018]

  * Client DoS due to large DH parameter ([CVE-2018-0732])
  * Cache timing vulnerability in RSA Key Generation ([CVE-2018-0737])

### Major changes between OpenSSL 1.0.2n and OpenSSL 1.0.2o [27 Mar 2018]

  * Constructed ASN.1 types with a recursive definition could exceed the
    stack ([CVE-2018-0739])

### Major changes between OpenSSL 1.0.2m and OpenSSL 1.0.2n [7 Dec 2017]

  * Read/write after SSL object in error state ([CVE-2017-3737])
  * rsaz_1024_mul_avx2 overflow bug on x86_64 ([CVE-2017-3738])

### Major changes between OpenSSL 1.0.2l and OpenSSL 1.0.2m [2 Nov 2017]

  * bn_sqrx8x_internal carry bug on x86_64 ([CVE-2017-3736])
  * Malformed X.509 IPAddressFamily could cause OOB read ([CVE-2017-3735])

### Major changes between OpenSSL 1.0.2k and OpenSSL 1.0.2l [25 May 2017]

  * config now recognises 64-bit mingw and chooses mingw64 instead of mingw

### Major changes between OpenSSL 1.0.2j and OpenSSL 1.0.2k [26 Jan 2017]

  * Truncated packet could crash via OOB read ([CVE-2017-3731])
  * BN_mod_exp may produce incorrect results on x86_64 ([CVE-2017-3732])
  * Montgomery multiplication may produce incorrect results ([CVE-2016-7055])

### Major changes between OpenSSL 1.0.2i and OpenSSL 1.0.2j [26 Sep 2016]

  * Missing CRL sanity check ([CVE-2016-7052])

### Major changes between OpenSSL 1.0.2h and OpenSSL 1.0.2i [22 Sep 2016]

  * OCSP Status Request extension unbounded memory growth ([CVE-2016-6304])
  * SWEET32 Mitigation ([CVE-2016-2183])
  * OOB write in MDC2_Update() ([CVE-2016-6303])
  * Malformed SHA512 ticket DoS ([CVE-2016-6302])
  * OOB write in BN_bn2dec() ([CVE-2016-2182])
  * OOB read in TS_OBJ_print_bio() ([CVE-2016-2180])
  * Pointer arithmetic undefined behaviour ([CVE-2016-2177])
  * Constant time flag not preserved in DSA signing ([CVE-2016-2178])
  * DTLS buffered message DoS ([CVE-2016-2179])
  * DTLS replay protection DoS ([CVE-2016-2181])
  * Certificate message OOB reads ([CVE-2016-6306])

### Major changes between OpenSSL 1.0.2g and OpenSSL 1.0.2h [3 May 2016]

  * Prevent padding oracle in AES-NI CBC MAC check ([CVE-2016-2107])
  * Fix EVP_EncodeUpdate overflow ([CVE-2016-2105])
  * Fix EVP_EncryptUpdate overflow ([CVE-2016-2106])
  * Prevent ASN.1 BIO excessive memory allocation ([CVE-2016-2109])
  * EBCDIC overread ([CVE-2016-2176])
  * Modify behavior of ALPN to invoke callback after SNI/servername
    callback, such that updates to the SSL_CTX affect ALPN.
  * Remove LOW from the DEFAULT cipher list.  This removes singles DES from
    the default.
  * Only remove the SSLv2 methods with the no-ssl2-method option.

### Major changes between OpenSSL 1.0.2f and OpenSSL 1.0.2g [1 Mar 2016]

  * Disable weak ciphers in SSLv3 and up in default builds of OpenSSL.
  * Disable SSLv2 default build, default negotiation and weak ciphers
    ([CVE-2016-0800])
  * Fix a double-free in DSA code ([CVE-2016-0705])
  * Disable SRP fake user seed to address a server memory leak
    ([CVE-2016-0798])
  * Fix BN_hex2bn/BN_dec2bn NULL pointer deref/heap corruption
    ([CVE-2016-0797])
  * Fix memory issues in BIO_*printf functions ([CVE-2016-0799])
  * Fix side channel attack on modular exponentiation ([CVE-2016-0702])

### Major changes between OpenSSL 1.0.2e and OpenSSL 1.0.2f [28 Jan 2016]

  * DH small subgroups ([CVE-2016-0701])
  * SSLv2 doesn't block disabled ciphers ([CVE-2015-3197])

### Major changes between OpenSSL 1.0.2d and OpenSSL 1.0.2e [3 Dec 2015]

  * BN_mod_exp may produce incorrect results on x86_64 ([CVE-2015-3193])
  * Certificate verify crash with missing PSS parameter ([CVE-2015-3194])
  * X509_ATTRIBUTE memory leak ([CVE-2015-3195])
  * Rewrite EVP_DecodeUpdate (base64 decoding) to fix several bugs
  * In DSA_generate_parameters_ex, if the provided seed is too short,
    return an error

### Major changes between OpenSSL 1.0.2c and OpenSSL 1.0.2d [9 Jul 2015]

  * Alternate chains certificate forgery ([CVE-2015-1793])
  * Race condition handling PSK identify hint ([CVE-2015-3196])

### Major changes between OpenSSL 1.0.2b and OpenSSL 1.0.2c [12 Jun 2015]

  * Fix HMAC ABI incompatibility

### Major changes between OpenSSL 1.0.2a and OpenSSL 1.0.2b [11 Jun 2015]

  * Malformed ECParameters causes infinite loop ([CVE-2015-1788])
  * Exploitable out-of-bounds read in X509_cmp_time ([CVE-2015-1789])
  * PKCS7 crash with missing EnvelopedContent ([CVE-2015-1790])
  * CMS verify infinite loop with unknown hash function ([CVE-2015-1792])
  * Race condition handling NewSessionTicket ([CVE-2015-1791])

### Major changes between OpenSSL 1.0.2 and OpenSSL 1.0.2a [19 Mar 2015]

  * OpenSSL 1.0.2 ClientHello sigalgs DoS fix ([CVE-2015-0291])
  * Multiblock corrupted pointer fix ([CVE-2015-0290])
  * Segmentation fault in DTLSv1_listen fix ([CVE-2015-0207])
  * Segmentation fault in ASN1_TYPE_cmp fix ([CVE-2015-0286])
  * Segmentation fault for invalid PSS parameters fix ([CVE-2015-0208])
  * ASN.1 structure reuse memory corruption fix ([CVE-2015-0287])
  * PKCS7 NULL pointer dereferences fix ([CVE-2015-0289])
  * DoS via reachable assert in SSLv2 servers fix ([CVE-2015-0293])
  * Empty CKE with client auth and DHE fix ([CVE-2015-1787])
  * Handshake with unseeded PRNG fix ([CVE-2015-0285])
  * Use After Free following d2i_ECPrivatekey error fix ([CVE-2015-0209])
  * X509_to_X509_REQ NULL pointer deref fix ([CVE-2015-0288])
  * Removed the export ciphers from the DEFAULT ciphers

### Major changes between OpenSSL 1.0.1l and OpenSSL 1.0.2 [22 Jan 2015]

  * Suite B support for TLS 1.2 and DTLS 1.2
  * Support for DTLS 1.2
  * TLS automatic EC curve selection.
  * API to set TLS supported signature algorithms and curves
  * SSL_CONF configuration API.
  * TLS Brainpool support.
  * ALPN support.
  * CMS support for RSA-PSS, RSA-OAEP, ECDH and X9.42 DH.

OpenSSL 1.0.1
-------------

### Major changes between OpenSSL 1.0.1t and OpenSSL 1.0.1u [22 Sep 2016]

  * OCSP Status Request extension unbounded memory growth ([CVE-2016-6304])
  * SWEET32 Mitigation ([CVE-2016-2183])
  * OOB write in MDC2_Update() ([CVE-2016-6303])
  * Malformed SHA512 ticket DoS ([CVE-2016-6302])
  * OOB write in BN_bn2dec() ([CVE-2016-2182])
  * OOB read in TS_OBJ_print_bio() ([CVE-2016-2180])
  * Pointer arithmetic undefined behaviour ([CVE-2016-2177])
  * Constant time flag not preserved in DSA signing ([CVE-2016-2178])
  * DTLS buffered message DoS ([CVE-2016-2179])
  * DTLS replay protection DoS ([CVE-2016-2181])
  * Certificate message OOB reads ([CVE-2016-6306])

### Major changes between OpenSSL 1.0.1s and OpenSSL 1.0.1t [3 May 2016]

  * Prevent padding oracle in AES-NI CBC MAC check ([CVE-2016-2107])
  * Fix EVP_EncodeUpdate overflow ([CVE-2016-2105])
  * Fix EVP_EncryptUpdate overflow ([CVE-2016-2106])
  * Prevent ASN.1 BIO excessive memory allocation ([CVE-2016-2109])
  * EBCDIC overread ([CVE-2016-2176])
  * Modify behavior of ALPN to invoke callback after SNI/servername
    callback, such that updates to the SSL_CTX affect ALPN.
  * Remove LOW from the DEFAULT cipher list.  This removes singles DES from
    the default.
  * Only remove the SSLv2 methods with the no-ssl2-method option.

### Major changes between OpenSSL 1.0.1r and OpenSSL 1.0.1s [1 Mar 2016]

  * Disable weak ciphers in SSLv3 and up in default builds of OpenSSL.
  * Disable SSLv2 default build, default negotiation and weak ciphers
    ([CVE-2016-0800])
  * Fix a double-free in DSA code ([CVE-2016-0705])
  * Disable SRP fake user seed to address a server memory leak
    ([CVE-2016-0798])
  * Fix BN_hex2bn/BN_dec2bn NULL pointer deref/heap corruption
    ([CVE-2016-0797])
  * Fix memory issues in BIO_*printf functions ([CVE-2016-0799])
  * Fix side channel attack on modular exponentiation ([CVE-2016-0702])

### Major changes between OpenSSL 1.0.1q and OpenSSL 1.0.1r [28 Jan 2016]

  * Protection for DH small subgroup attacks
  * SSLv2 doesn't block disabled ciphers ([CVE-2015-3197])

### Major changes between OpenSSL 1.0.1p and OpenSSL 1.0.1q [3 Dec 2015]

  * Certificate verify crash with missing PSS parameter ([CVE-2015-3194])
  * X509_ATTRIBUTE memory leak ([CVE-2015-3195])
  * Rewrite EVP_DecodeUpdate (base64 decoding) to fix several bugs
  * In DSA_generate_parameters_ex, if the provided seed is too short,
    return an error

### Major changes between OpenSSL 1.0.1o and OpenSSL 1.0.1p [9 Jul 2015]

  * Alternate chains certificate forgery ([CVE-2015-1793])
  * Race condition handling PSK identify hint ([CVE-2015-3196])

### Major changes between OpenSSL 1.0.1n and OpenSSL 1.0.1o [12 Jun 2015]

  * Fix HMAC ABI incompatibility

### Major changes between OpenSSL 1.0.1m and OpenSSL 1.0.1n [11 Jun 2015]

  * Malformed ECParameters causes infinite loop ([CVE-2015-1788])
  * Exploitable out-of-bounds read in X509_cmp_time ([CVE-2015-1789])
  * PKCS7 crash with missing EnvelopedContent ([CVE-2015-1790])
  * CMS verify infinite loop with unknown hash function ([CVE-2015-1792])
  * Race condition handling NewSessionTicket ([CVE-2015-1791])

### Major changes between OpenSSL 1.0.1l and OpenSSL 1.0.1m [19 Mar 2015]

  * Segmentation fault in ASN1_TYPE_cmp fix ([CVE-2015-0286])
  * ASN.1 structure reuse memory corruption fix ([CVE-2015-0287])
  * PKCS7 NULL pointer dereferences fix ([CVE-2015-0289])
  * DoS via reachable assert in SSLv2 servers fix ([CVE-2015-0293])
  * Use After Free following d2i_ECPrivatekey error fix ([CVE-2015-0209])
  * X509_to_X509_REQ NULL pointer deref fix ([CVE-2015-0288])
  * Removed the export ciphers from the DEFAULT ciphers

### Major changes between OpenSSL 1.0.1k and OpenSSL 1.0.1l [15 Jan 2015]

  * Build fixes for the Windows and OpenVMS platforms

### Major changes between OpenSSL 1.0.1j and OpenSSL 1.0.1k [8 Jan 2015]

  * Fix for [CVE-2014-3571]
  * Fix for [CVE-2015-0206]
  * Fix for [CVE-2014-3569]
  * Fix for [CVE-2014-3572]
  * Fix for [CVE-2015-0204]
  * Fix for [CVE-2015-0205]
  * Fix for [CVE-2014-8275]
  * Fix for [CVE-2014-3570]

### Major changes between OpenSSL 1.0.1i and OpenSSL 1.0.1j [15 Oct 2014]

  * Fix for [CVE-2014-3513]
  * Fix for [CVE-2014-3567]
  * Mitigation for [CVE-2014-3566] (SSL protocol vulnerability)
  * Fix for [CVE-2014-3568]

### Major changes between OpenSSL 1.0.1h and OpenSSL 1.0.1i [6 Aug 2014]

  * Fix for [CVE-2014-3512]
  * Fix for [CVE-2014-3511]
  * Fix for [CVE-2014-3510]
  * Fix for [CVE-2014-3507]
  * Fix for [CVE-2014-3506]
  * Fix for [CVE-2014-3505]
  * Fix for [CVE-2014-3509]
  * Fix for [CVE-2014-5139]
  * Fix for [CVE-2014-3508]

### Major changes between OpenSSL 1.0.1g and OpenSSL 1.0.1h [5 Jun 2014]

  * Fix for [CVE-2014-0224]
  * Fix for [CVE-2014-0221]
  * Fix for [CVE-2014-0198]
  * Fix for [CVE-2014-0195]
  * Fix for [CVE-2014-3470]
  * Fix for [CVE-2010-5298]

### Major changes between OpenSSL 1.0.1f and OpenSSL 1.0.1g [7 Apr 2014]

  * Fix for [CVE-2014-0160]
  * Add TLS padding extension workaround for broken servers.
  * Fix for [CVE-2014-0076]

### Major changes between OpenSSL 1.0.1e and OpenSSL 1.0.1f [6 Jan 2014]

  * Don't include gmt_unix_time in TLS server and client random values
  * Fix for TLS record tampering bug ([CVE-2013-4353])
  * Fix for TLS version checking bug ([CVE-2013-6449])
  * Fix for DTLS retransmission bug ([CVE-2013-6450])

### Major changes between OpenSSL 1.0.1d and OpenSSL 1.0.1e [11 Feb 2013]

  * Corrected fix for ([CVE-2013-0169])

### Major changes between OpenSSL 1.0.1c and OpenSSL 1.0.1d [4 Feb 2013]

  * Fix renegotiation in TLS 1.1, 1.2 by using the correct TLS version.
  * Include the fips configuration module.
  * Fix OCSP bad key DoS attack ([CVE-2013-0166])
  * Fix for SSL/TLS/DTLS CBC plaintext recovery attack ([CVE-2013-0169])
  * Fix for TLS AESNI record handling flaw ([CVE-2012-2686])

### Major changes between OpenSSL 1.0.1b and OpenSSL 1.0.1c [10 May 2012]

  * Fix TLS/DTLS record length checking bug ([CVE-2012-2333])
  * Don't attempt to use non-FIPS composite ciphers in FIPS mode.

### Major changes between OpenSSL 1.0.1a and OpenSSL 1.0.1b [26 Apr 2012]

  * Fix compilation error on non-x86 platforms.
  * Make FIPS capable OpenSSL ciphers work in non-FIPS mode.
  * Fix SSL_OP_NO_TLSv1_1 clash with SSL_OP_ALL in OpenSSL 1.0.0

### Major changes between OpenSSL 1.0.1 and OpenSSL 1.0.1a [19 Apr 2012]

  * Fix for ASN1 overflow bug ([CVE-2012-2110])
  * Workarounds for some servers that hang on long client hellos.
  * Fix SEGV in AES code.

### Major changes between OpenSSL 1.0.0h and OpenSSL 1.0.1 [14 Mar 2012]

  * TLS/DTLS heartbeat support.
  * SCTP support.
  * RFC 5705 TLS key material exporter.
  * RFC 5764 DTLS-SRTP negotiation.
  * Next Protocol Negotiation.
  * PSS signatures in certificates, requests and CRLs.
  * Support for password based recipient info for CMS.
  * Support TLS v1.2 and TLS v1.1.
  * Preliminary FIPS capability for unvalidated 2.0 FIPS module.
  * SRP support.

OpenSSL 1.0.0
-------------

### Major changes between OpenSSL 1.0.0s and OpenSSL 1.0.0t [3 Dec 2015]

  * X509_ATTRIBUTE memory leak (([CVE-2015-3195]))
  * Race condition handling PSK identify hint ([CVE-2015-3196])

### Major changes between OpenSSL 1.0.0r and OpenSSL 1.0.0s [11 Jun 2015]

  * Malformed ECParameters causes infinite loop ([CVE-2015-1788])
  * Exploitable out-of-bounds read in X509_cmp_time ([CVE-2015-1789])
  * PKCS7 crash with missing EnvelopedContent ([CVE-2015-1790])
  * CMS verify infinite loop with unknown hash function ([CVE-2015-1792])
  * Race condition handling NewSessionTicket ([CVE-2015-1791])

### Major changes between OpenSSL 1.0.0q and OpenSSL 1.0.0r [19 Mar 2015]

  * Segmentation fault in ASN1_TYPE_cmp fix ([CVE-2015-0286])
  * ASN.1 structure reuse memory corruption fix ([CVE-2015-0287])
  * PKCS7 NULL pointer dereferences fix ([CVE-2015-0289])
  * DoS via reachable assert in SSLv2 servers fix ([CVE-2015-0293])
  * Use After Free following d2i_ECPrivatekey error fix ([CVE-2015-0209])
  * X509_to_X509_REQ NULL pointer deref fix ([CVE-2015-0288])
  * Removed the export ciphers from the DEFAULT ciphers

### Major changes between OpenSSL 1.0.0p and OpenSSL 1.0.0q [15 Jan 2015]

  * Build fixes for the Windows and OpenVMS platforms

### Major changes between OpenSSL 1.0.0o and OpenSSL 1.0.0p [8 Jan 2015]

  * Fix for [CVE-2014-3571]
  * Fix for [CVE-2015-0206]
  * Fix for [CVE-2014-3569]
  * Fix for [CVE-2014-3572]
  * Fix for [CVE-2015-0204]
  * Fix for [CVE-2015-0205]
  * Fix for [CVE-2014-8275]
  * Fix for [CVE-2014-3570]

### Major changes between OpenSSL 1.0.0n and OpenSSL 1.0.0o [15 Oct 2014]

  * Fix for [CVE-2014-3513]
  * Fix for [CVE-2014-3567]
  * Mitigation for [CVE-2014-3566] (SSL protocol vulnerability)
  * Fix for [CVE-2014-3568]

### Major changes between OpenSSL 1.0.0m and OpenSSL 1.0.0n [6 Aug 2014]

  * Fix for [CVE-2014-3510]
  * Fix for [CVE-2014-3507]
  * Fix for [CVE-2014-3506]
  * Fix for [CVE-2014-3505]
  * Fix for [CVE-2014-3509]
  * Fix for [CVE-2014-3508]

  Known issues in OpenSSL 1.0.0m:

  * EAP-FAST and other applications using tls_session_secret_cb
    won't resume sessions. Fixed in 1.0.0n-dev
  * Compilation failure of s3_pkt.c on some platforms due to missing
    `<limits.h>` include. Fixed in 1.0.0n-dev

### Major changes between OpenSSL 1.0.0l and OpenSSL 1.0.0m [5 Jun 2014]

  * Fix for [CVE-2014-0224]
  * Fix for [CVE-2014-0221]
  * Fix for [CVE-2014-0198]
  * Fix for [CVE-2014-0195]
  * Fix for [CVE-2014-3470]
  * Fix for [CVE-2014-0076]
  * Fix for [CVE-2010-5298]

### Major changes between OpenSSL 1.0.0k and OpenSSL 1.0.0l [6 Jan 2014]

  * Fix for DTLS retransmission bug ([CVE-2013-6450])

### Major changes between OpenSSL 1.0.0j and OpenSSL 1.0.0k [5 Feb 2013]

  * Fix for SSL/TLS/DTLS CBC plaintext recovery attack ([CVE-2013-0169])
  * Fix OCSP bad key DoS attack ([CVE-2013-0166])

### Major changes between OpenSSL 1.0.0i and OpenSSL 1.0.0j [10 May 2012]

  * Fix DTLS record length checking bug ([CVE-2012-2333])

### Major changes between OpenSSL 1.0.0h and OpenSSL 1.0.0i [19 Apr 2012]

  * Fix for ASN1 overflow bug ([CVE-2012-2110])

### Major changes between OpenSSL 1.0.0g and OpenSSL 1.0.0h [12 Mar 2012]

  * Fix for CMS/PKCS#7 MMA ([CVE-2012-0884])
  * Corrected fix for ([CVE-2011-4619])
  * Various DTLS fixes.

### Major changes between OpenSSL 1.0.0f and OpenSSL 1.0.0g [18 Jan 2012]

  * Fix for DTLS DoS issue ([CVE-2012-0050])

### Major changes between OpenSSL 1.0.0e and OpenSSL 1.0.0f [4 Jan 2012]

  * Fix for DTLS plaintext recovery attack ([CVE-2011-4108])
  * Clear block padding bytes of SSL 3.0 records ([CVE-2011-4576])
  * Only allow one SGC handshake restart for SSL/TLS ([CVE-2011-4619])
  * Check parameters are not NULL in GOST ENGINE ([CVE-2012-0027])
  * Check for malformed RFC3779 data ([CVE-2011-4577])

### Major changes between OpenSSL 1.0.0d and OpenSSL 1.0.0e [6 Sep 2011]

  * Fix for CRL vulnerability issue ([CVE-2011-3207])
  * Fix for ECDH crashes ([CVE-2011-3210])
  * Protection against EC timing attacks.
  * Support ECDH ciphersuites for certificates using SHA2 algorithms.
  * Various DTLS fixes.

### Major changes between OpenSSL 1.0.0c and OpenSSL 1.0.0d [8 Feb 2011]

  * Fix for security issue ([CVE-2011-0014])

### Major changes between OpenSSL 1.0.0b and OpenSSL 1.0.0c [2 Dec 2010]

  * Fix for security issue ([CVE-2010-4180])
  * Fix for ([CVE-2010-4252])
  * Fix mishandling of absent EC point format extension.
  * Fix various platform compilation issues.
  * Corrected fix for security issue ([CVE-2010-3864]).

### Major changes between OpenSSL 1.0.0a and OpenSSL 1.0.0b [16 Nov 2010]

  * Fix for security issue ([CVE-2010-3864]).
  * Fix for ([CVE-2010-2939])
  * Fix WIN32 build system for GOST ENGINE.

### Major changes between OpenSSL 1.0.0 and OpenSSL 1.0.0a [1 Jun 2010]

  * Fix for security issue ([CVE-2010-1633]).
  * GOST MAC and CFB fixes.

### Major changes between OpenSSL 0.9.8n and OpenSSL 1.0.0 [29 Mar 2010]

  * RFC3280 path validation: sufficient to process PKITS tests.
  * Integrated support for PVK files and keyblobs.
  * Change default private key format to PKCS#8.
  * CMS support: able to process all examples in RFC4134
  * Streaming ASN1 encode support for PKCS#7 and CMS.
  * Multiple signer and signer add support for PKCS#7 and CMS.
  * ASN1 printing support.
  * Whirlpool hash algorithm added.
  * RFC3161 time stamp support.
  * New generalised public key API supporting ENGINE based algorithms.
  * New generalised public key API utilities.
  * New ENGINE supporting GOST algorithms.
  * SSL/TLS GOST ciphersuite support.
  * PKCS#7 and CMS GOST support.
  * RFC4279 PSK ciphersuite support.
  * Supported points format extension for ECC ciphersuites.
  * ecdsa-with-SHA224/256/384/512 signature types.
  * dsa-with-SHA224 and dsa-with-SHA256 signature types.
  * Opaque PRF Input TLS extension support.
  * Updated time routines to avoid OS limitations.

OpenSSL 0.9.x
-------------

### Major changes between OpenSSL 0.9.8m and OpenSSL 0.9.8n [24 Mar 2010]

  * CFB cipher definition fixes.
  * Fix security issues [CVE-2010-0740] and [CVE-2010-0433].

### Major changes between OpenSSL 0.9.8l and OpenSSL 0.9.8m [25 Feb 2010]

  * Cipher definition fixes.
  * Workaround for slow RAND_poll() on some WIN32 versions.
  * Remove MD2 from algorithm tables.
  * SPKAC handling fixes.
  * Support for RFC5746 TLS renegotiation extension.
  * Compression memory leak fixed.
  * Compression session resumption fixed.
  * Ticket and SNI coexistence fixes.
  * Many fixes to DTLS handling.

### Major changes between OpenSSL 0.9.8k and OpenSSL 0.9.8l [5 Nov 2009]

  * Temporary work around for [CVE-2009-3555]: disable renegotiation.

### Major changes between OpenSSL 0.9.8j and OpenSSL 0.9.8k [25 Mar 2009]

  * Fix various build issues.
  * Fix security issues [CVE-2009-0590], [CVE-2009-0591], [CVE-2009-0789]

### Major changes between OpenSSL 0.9.8i and OpenSSL 0.9.8j [7 Jan 2009]

  * Fix security issue ([CVE-2008-5077])
  * Merge FIPS 140-2 branch code.

### Major changes between OpenSSL 0.9.8g and OpenSSL 0.9.8h [28 May 2008]

  * CryptoAPI ENGINE support.
  * Various precautionary measures.
  * Fix for bugs affecting certificate request creation.
  * Support for local machine keyset attribute in PKCS#12 files.

### Major changes between OpenSSL 0.9.8f and OpenSSL 0.9.8g [19 Oct 2007]

  * Backport of CMS functionality to 0.9.8.
  * Fixes for bugs introduced with 0.9.8f.

### Major changes between OpenSSL 0.9.8e and OpenSSL 0.9.8f [11 Oct 2007]

  * Add gcc 4.2 support.
  * Add support for AES and SSE2 assembly language optimization
    for VC++ build.
  * Support for RFC4507bis and server name extensions if explicitly
    selected at compile time.
  * DTLS improvements.
  * RFC4507bis support.
  * TLS Extensions support.

### Major changes between OpenSSL 0.9.8d and OpenSSL 0.9.8e [23 Feb 2007]

  * Various ciphersuite selection fixes.
  * RFC3779 support.

### Major changes between OpenSSL 0.9.8c and OpenSSL 0.9.8d [28 Sep 2006]

  * Introduce limits to prevent malicious key DoS  ([CVE-2006-2940])
  * Fix security issues [CVE-2006-2937], [CVE-2006-3737], [CVE-2006-4343]
  * Changes to ciphersuite selection algorithm

### Major changes between OpenSSL 0.9.8b and OpenSSL 0.9.8c [5 Sep 2006]

  * Fix Daniel Bleichenbacher forged signature attack, [CVE-2006-4339]
  * New cipher Camellia

### Major changes between OpenSSL 0.9.8a and OpenSSL 0.9.8b [4 May 2006]

  * Cipher string fixes.
  * Fixes for VC++ 2005.
  * Updated ECC cipher suite support.
  * New functions EVP_CIPHER_CTX_new() and EVP_CIPHER_CTX_free().
  * Zlib compression usage fixes.
  * Built in dynamic engine compilation support on Win32.
  * Fixes auto dynamic engine loading in Win32.

### Major changes between OpenSSL 0.9.8 and OpenSSL 0.9.8a [11 Oct 2005]

  * Fix potential SSL 2.0 rollback ([CVE-2005-2969])
  * Extended Windows CE support

### Major changes between OpenSSL 0.9.7g and OpenSSL 0.9.8 [5 Jul 2005]

  * Major work on the BIGNUM library for higher efficiency and to
    make operations more streamlined and less contradictory.  This
    is the result of a major audit of the BIGNUM library.
  * Addition of BIGNUM functions for fields GF(2^m) and NIST
    curves, to support the Elliptic Crypto functions.
  * Major work on Elliptic Crypto; ECDH and ECDSA added, including
    the use through EVP, X509 and ENGINE.
  * New ASN.1 mini-compiler that's usable through the OpenSSL
    configuration file.
  * Added support for ASN.1 indefinite length constructed encoding.
  * New PKCS#12 'medium level' API to manipulate PKCS#12 files.
  * Complete rework of shared library construction and linking
    programs with shared or static libraries, through a separate
    Makefile.shared.
  * Rework of the passing of parameters from one Makefile to another.
  * Changed ENGINE framework to load dynamic engine modules
    automatically from specifically given directories.
  * New structure and ASN.1 functions for CertificatePair.
  * Changed the ZLIB compression method to be stateful.
  * Changed the key-generation and primality testing "progress"
    mechanism to take a structure that contains the ticker
    function and an argument.
  * New engine module: GMP (performs private key exponentiation).
  * New engine module: VIA PadLOck ACE extension in VIA C3
    Nehemiah processors.
  * Added support for IPv6 addresses in certificate extensions.
    See RFC 1884, section 2.2.
  * Added support for certificate policy mappings, policy
    constraints and name constraints.
  * Added support for multi-valued AVAs in the OpenSSL
    configuration file.
  * Added support for multiple certificates with the same subject
    in the 'openssl ca' index file.
  * Make it possible to create self-signed certificates using
    'openssl ca -selfsign'.
  * Make it possible to generate a serial number file with
    'openssl ca -create_serial'.
  * New binary search functions with extended functionality.
  * New BUF functions.
  * New STORE structure and library to provide an interface to all
    sorts of data repositories.  Supports storage of public and
    private keys, certificates, CRLs, numbers and arbitrary blobs.
    This library is unfortunately unfinished and unused within
    OpenSSL.
  * New control functions for the error stack.
  * Changed the PKCS#7 library to support one-pass S/MIME
    processing.
  * Added the possibility to compile without old deprecated
    functionality with the OPENSSL_NO_DEPRECATED macro or the
    'no-deprecated' argument to the config and Configure scripts.
  * Constification of all ASN.1 conversion functions, and other
    affected functions.
  * Improved platform support for PowerPC.
  * New FIPS 180-2 algorithms (SHA-224, -256, -384 and -512).
  * New X509_VERIFY_PARAM structure to support parameterisation
  of X.509 path validation.
  * Major overhaul of RC4 performance on Intel P4, IA-64 and
    AMD64.
  * Changed the Configure script to have some algorithms disabled
    by default.  Those can be explicitly enabled with the new
    argument form 'enable-xxx'.
  * Change the default digest in 'openssl' commands from MD5 to
    SHA-1.
  * Added support for DTLS.
  * New BIGNUM blinding.
  * Added support for the RSA-PSS encryption scheme
  * Added support for the RSA X.931 padding.
  * Added support for BSD sockets on NetWare.
  * Added support for files larger than 2GB.
  * Added initial support for Win64.
  * Added alternate pkg-config files.

### Major changes between OpenSSL 0.9.7l and OpenSSL 0.9.7m [23 Feb 2007]

  * FIPS 1.1.1 module linking.
  * Various ciphersuite selection fixes.

### Major changes between OpenSSL 0.9.7k and OpenSSL 0.9.7l [28 Sep 2006]

  * Introduce limits to prevent malicious key DoS  ([CVE-2006-2940])
  * Fix security issues [CVE-2006-2937], [CVE-2006-3737], [CVE-2006-4343]

### Major changes between OpenSSL 0.9.7j and OpenSSL 0.9.7k [5 Sep 2006]

  * Fix Daniel Bleichenbacher forged signature attack, [CVE-2006-4339]

### Major changes between OpenSSL 0.9.7i and OpenSSL 0.9.7j [4 May 2006]

  * Visual C++ 2005 fixes.
  * Update Windows build system for FIPS.

### Major changes between OpenSSL 0.9.7h and OpenSSL 0.9.7i [14 Oct 2005]

  * Give EVP_MAX_MD_SIZE its old value, except for a FIPS build.

### Major changes between OpenSSL 0.9.7g and OpenSSL 0.9.7h [11 Oct 2005]

  * Fix SSL 2.0 Rollback ([CVE-2005-2969])
  * Allow use of fixed-length exponent on DSA signing
  * Default fixed-window RSA, DSA, DH private-key operations

### Major changes between OpenSSL 0.9.7f and OpenSSL 0.9.7g [11 Apr 2005]

  * More compilation issues fixed.
  * Adaptation to more modern Kerberos API.
  * Enhanced or corrected configuration for Solaris64, Mingw and Cygwin.
  * Enhanced x86_64 assembler BIGNUM module.
  * More constification.
  * Added processing of proxy certificates (RFC 3820).

### Major changes between OpenSSL 0.9.7e and OpenSSL 0.9.7f [22 Mar 2005]

  * Several compilation issues fixed.
  * Many memory allocation failure checks added.
  * Improved comparison of X509 Name type.
  * Mandatory basic checks on certificates.
  * Performance improvements.

### Major changes between OpenSSL 0.9.7d and OpenSSL 0.9.7e [25 Oct 2004]

  * Fix race condition in CRL checking code.
  * Fixes to PKCS#7 (S/MIME) code.

### Major changes between OpenSSL 0.9.7c and OpenSSL 0.9.7d [17 Mar 2004]

  * Security: Fix Kerberos ciphersuite SSL/TLS handshaking bug
  * Security: Fix null-pointer assignment in do_change_cipher_spec()
  * Allow multiple active certificates with same subject in CA index
  * Multiple X509 verification fixes
  * Speed up HMAC and other operations

### Major changes between OpenSSL 0.9.7b and OpenSSL 0.9.7c [30 Sep 2003]

  * Security: fix various ASN1 parsing bugs.
  * New -ignore_err option to OCSP utility.
  * Various interop and bug fixes in S/MIME code.
  * SSL/TLS protocol fix for unrequested client certificates.

### Major changes between OpenSSL 0.9.7a and OpenSSL 0.9.7b [10 Apr 2003]

  * Security: counter the Klima-Pokorny-Rosa extension of
    Bleichbacher's attack
  * Security: make RSA blinding default.
  * Configuration: Irix fixes, AIX fixes, better mingw support.
  * Support for new platforms: linux-ia64-ecc.
  * Build: shared library support fixes.
  * ASN.1: treat domainComponent correctly.
  * Documentation: fixes and additions.

### Major changes between OpenSSL 0.9.7 and OpenSSL 0.9.7a [19 Feb 2003]

  * Security: Important security related bugfixes.
  * Enhanced compatibility with MIT Kerberos.
  * Can be built without the ENGINE framework.
  * IA32 assembler enhancements.
  * Support for new platforms: FreeBSD/IA64 and FreeBSD/Sparc64.
  * Configuration: the no-err option now works properly.
  * SSL/TLS: now handles manual certificate chain building.
  * SSL/TLS: certain session ID malfunctions corrected.

### Major changes between OpenSSL 0.9.6 and OpenSSL 0.9.7 [30 Dec 2002]

  * New library section OCSP.
  * Complete rewrite of ASN1 code.
  * CRL checking in verify code and openssl utility.
  * Extension copying in 'ca' utility.
  * Flexible display options in 'ca' utility.
  * Provisional support for international characters with UTF8.
  * Support for external crypto devices ('engine') is no longer
    a separate distribution.
  * New elliptic curve library section.
  * New AES (Rijndael) library section.
  * Support for new platforms: Windows CE, Tandem OSS, A/UX, AIX 64-bit,
    Linux x86_64, Linux 64-bit on Sparc v9
  * Extended support for some platforms: VxWorks
  * Enhanced support for shared libraries.
  * Now only builds PIC code when shared library support is requested.
  * Support for pkg-config.
  * Lots of new manuals.
  * Makes symbolic links to or copies of manuals to cover all described
    functions.
  * Change DES API to clean up the namespace (some applications link also
    against libdes providing similar functions having the same name).
    Provide macros for backward compatibility (will be removed in the
    future).
  * Unify handling of cryptographic algorithms (software and engine)
    to be available via EVP routines for asymmetric and symmetric ciphers.
  * NCONF: new configuration handling routines.
  * Change API to use more 'const' modifiers to improve error checking
    and help optimizers.
  * Finally remove references to RSAref.
  * Reworked parts of the BIGNUM code.
  * Support for new engines: Broadcom ubsec, Accelerated Encryption
    Processing, IBM 4758.
  * A few new engines added in the demos area.
  * Extended and corrected OID (object identifier) table.
  * PRNG: query at more locations for a random device, automatic query for
    EGD style random sources at several locations.
  * SSL/TLS: allow optional cipher choice according to server's preference.
  * SSL/TLS: allow server to explicitly set new session ids.
  * SSL/TLS: support Kerberos cipher suites (RFC2712).
    Only supports MIT Kerberos for now.
  * SSL/TLS: allow more precise control of renegotiations and sessions.
  * SSL/TLS: add callback to retrieve SSL/TLS messages.
  * SSL/TLS: support AES cipher suites (RFC3268).

### Major changes between OpenSSL 0.9.6j and OpenSSL 0.9.6k [30 Sep 2003]

  * Security: fix various ASN1 parsing bugs.
  * SSL/TLS protocol fix for unrequested client certificates.

### Major changes between OpenSSL 0.9.6i and OpenSSL 0.9.6j [10 Apr 2003]

  * Security: counter the Klima-Pokorny-Rosa extension of
    Bleichbacher's attack
  * Security: make RSA blinding default.
  * Build: shared library support fixes.

### Major changes between OpenSSL 0.9.6h and OpenSSL 0.9.6i [19 Feb 2003]

  * Important security related bugfixes.

### Major changes between OpenSSL 0.9.6g and OpenSSL 0.9.6h [5 Dec 2002]

  * New configuration targets for Tandem OSS and A/UX.
  * New OIDs for Microsoft attributes.
  * Better handling of SSL session caching.
  * Better comparison of distinguished names.
  * Better handling of shared libraries in a mixed GNU/non-GNU environment.
  * Support assembler code with Borland C.
  * Fixes for length problems.
  * Fixes for uninitialised variables.
  * Fixes for memory leaks, some unusual crashes and some race conditions.
  * Fixes for smaller building problems.
  * Updates of manuals, FAQ and other instructive documents.

### Major changes between OpenSSL 0.9.6f and OpenSSL 0.9.6g [9 Aug 2002]

  * Important building fixes on Unix.

### Major changes between OpenSSL 0.9.6e and OpenSSL 0.9.6f [8 Aug 2002]

  * Various important bugfixes.

### Major changes between OpenSSL 0.9.6d and OpenSSL 0.9.6e [30 Jul 2002]

  * Important security related bugfixes.
  * Various SSL/TLS library bugfixes.

### Major changes between OpenSSL 0.9.6c and OpenSSL 0.9.6d [9 May 2002]

  * Various SSL/TLS library bugfixes.
  * Fix DH parameter generation for 'non-standard' generators.

### Major changes between OpenSSL 0.9.6b and OpenSSL 0.9.6c [21 Dec 2001]

  * Various SSL/TLS library bugfixes.
  * BIGNUM library fixes.
  * RSA OAEP and random number generation fixes.
  * Object identifiers corrected and added.
  * Add assembler BN routines for IA64.
  * Add support for OS/390 Unix, UnixWare with gcc, OpenUNIX 8,
    MIPS Linux; shared library support for Irix, HP-UX.
  * Add crypto accelerator support for AEP, Baltimore SureWare,
    Broadcom and Cryptographic Appliance's keyserver
    [in 0.9.6c-engine release].

### Major changes between OpenSSL 0.9.6a and OpenSSL 0.9.6b [9 Jul 2001]

  * Security fix: PRNG improvements.
  * Security fix: RSA OAEP check.
  * Security fix: Reinsert and fix countermeasure to Bleichbacher's
    attack.
  * MIPS bug fix in BIGNUM.
  * Bug fix in "openssl enc".
  * Bug fix in X.509 printing routine.
  * Bug fix in DSA verification routine and DSA S/MIME verification.
  * Bug fix to make PRNG thread-safe.
  * Bug fix in RAND_file_name().
  * Bug fix in compatibility mode trust settings.
  * Bug fix in blowfish EVP.
  * Increase default size for BIO buffering filter.
  * Compatibility fixes in some scripts.

### Major changes between OpenSSL 0.9.6 and OpenSSL 0.9.6a [5 Apr 2001]

  * Security fix: change behavior of OpenSSL to avoid using
    environment variables when running as root.
  * Security fix: check the result of RSA-CRT to reduce the
    possibility of deducing the private key from an incorrectly
    calculated signature.
  * Security fix: prevent Bleichenbacher's DSA attack.
  * Security fix: Zero the premaster secret after deriving the
    master secret in DH ciphersuites.
  * Reimplement SSL_peek(), which had various problems.
  * Compatibility fix: the function des_encrypt() renamed to
    des_encrypt1() to avoid clashes with some Unixen libc.
  * Bug fixes for Win32, HP/UX and Irix.
  * Bug fixes in BIGNUM, SSL, PKCS#7, PKCS#12, X.509, CONF and
    memory checking routines.
  * Bug fixes for RSA operations in threaded environments.
  * Bug fixes in misc. openssl applications.
  * Remove a few potential memory leaks.
  * Add tighter checks of BIGNUM routines.
  * Shared library support has been reworked for generality.
  * More documentation.
  * New function BN_rand_range().
  * Add "-rand" option to openssl s_client and s_server.

### Major changes between OpenSSL 0.9.5a and OpenSSL 0.9.6 [10 Oct 2000]

  * Some documentation for BIO and SSL libraries.
  * Enhanced chain verification using key identifiers.
  * New sign and verify options to 'dgst' application.
  * Support for DER and PEM encoded messages in 'smime' application.
  * New 'rsautl' application, low-level RSA utility.
  * MD4 now included.
  * Bugfix for SSL rollback padding check.
  * Support for external crypto devices [1].
  * Enhanced EVP interface.

  [1] The support for external crypto devices is currently a separate
      distribution.  See the file README-Engine.md.

### Major changes between OpenSSL 0.9.5 and OpenSSL 0.9.5a [1 Apr 2000]

  * Bug fixes for Win32, SuSE Linux, NeXTSTEP and FreeBSD 2.2.8
  * Shared library support for HPUX and Solaris-gcc
  * Support of Linux/IA64
  * Assembler support for Mingw32
  * New 'rand' application
  * New way to check for existence of algorithms from scripts

### Major changes between OpenSSL 0.9.4 and OpenSSL 0.9.5 [25 May 2000]

  * S/MIME support in new 'smime' command
  * Documentation for the OpenSSL command line application
  * Automation of 'req' application
  * Fixes to make s_client, s_server work under Windows
  * Support for multiple fieldnames in SPKACs
  * New SPKAC command line utility and associated library functions
  * Options to allow passwords to be obtained from various sources
  * New public key PEM format and options to handle it
  * Many other fixes and enhancements to command line utilities
  * Usable certificate chain verification
  * Certificate purpose checking
  * Certificate trust settings
  * Support of authority information access extension
  * Extensions in certificate requests
  * Simplified X509 name and attribute routines
  * Initial (incomplete) support for international character sets
  * New DH_METHOD, DSA_METHOD and enhanced RSA_METHOD
  * Read only memory BIOs and simplified creation function
  * TLS/SSL protocol bugfixes: Accept TLS 'client hello' in SSL 3.0
    record; allow fragmentation and interleaving of handshake and other
    data
  * TLS/SSL code now "tolerates" MS SGC
  * Work around for Netscape client certificate hang bug
  * RSA_NULL option that removes RSA patent code but keeps other
    RSA functionality
  * Memory leak detection now allows applications to add extra information
    via a per-thread stack
  * PRNG robustness improved
  * EGD support
  * BIGNUM library bug fixes
  * Faster DSA parameter generation
  * Enhanced support for Alpha Linux
  * Experimental macOS support

### Major changes between OpenSSL 0.9.3 and OpenSSL 0.9.4 [9 Aug 1999]

  * Transparent support for PKCS#8 format private keys: these are used
    by several software packages and are more secure than the standard
    form
  * PKCS#5 v2.0 implementation
  * Password callbacks have a new void * argument for application data
  * Avoid various memory leaks
  * New pipe-like BIO that allows using the SSL library when actual I/O
    must be handled by the application (BIO pair)

### Major changes between OpenSSL 0.9.2b and OpenSSL 0.9.3 [24 May 1999]

  * Lots of enhancements and cleanups to the Configuration mechanism
  * RSA OEAP related fixes
  * Added "openssl ca -revoke" option for revoking a certificate
  * Source cleanups: const correctness, type-safe stacks and ASN.1 SETs
  * Source tree cleanups: removed lots of obsolete files
  * Thawte SXNet, certificate policies and CRL distribution points
    extension support
  * Preliminary (experimental) S/MIME support
  * Support for ASN.1 UTF8String and VisibleString
  * Full integration of PKCS#12 code
  * Sparc assembler bignum implementation, optimized hash functions
  * Option to disable selected ciphers

### Major changes between OpenSSL 0.9.1c and OpenSSL 0.9.2b [22 Mar 1999]

  * Fixed a security hole related to session resumption
  * Fixed RSA encryption routines for the p < q case
  * "ALL" in cipher lists now means "everything except NULL ciphers"
  * Support for Triple-DES CBCM cipher
  * Support of Optimal Asymmetric Encryption Padding (OAEP) for RSA
  * First support for new TLSv1 ciphers
  * Added a few new BIOs (syslog BIO, reliable BIO)
  * Extended support for DSA certificate/keys.
  * Extended support for Certificate Signing Requests (CSR)
  * Initial support for X.509v3 extensions
  * Extended support for compression inside the SSL record layer
  * Overhauled Win32 builds
  * Cleanups and fixes to the Big Number (BN) library
  * Support for ASN.1 GeneralizedTime
  * Split ASN.1 SETs from SEQUENCEs
  * ASN1 and PEM support for Netscape Certificate Sequences
  * Overhauled Perl interface
  * Lots of source tree cleanups.
  * Lots of memory leak fixes.
  * Lots of bug fixes.

### Major changes between SSLeay 0.9.0b and OpenSSL 0.9.1c [23 Dec 1998]

  * Integration of the popular NO_RSA/NO_DSA patches
  * Initial support for compression inside the SSL record layer
  * Added BIO proxy and filtering functionality
  * Extended Big Number (BN) library
  * Added RIPE MD160 message digest
  * Added support for RC2/64bit cipher
  * Extended ASN.1 parser routines
  * Adjustments of the source tree for CVS
  * Support for various new platforms

<!-- Links -->

[CVE-2024-6119]: https://www.openssl.org/news/vulnerabilities.html#CVE-2024-6119
[CVE-2024-5535]: https://www.openssl.org/news/vulnerabilities.html#CVE-2024-5535
[CVE-2024-4741]: https://www.openssl.org/news/vulnerabilities.html#CVE-2024-4741
[CVE-2024-4603]: https://www.openssl.org/news/vulnerabilities.html#CVE-2024-4603
[CVE-2024-2511]: https://www.openssl.org/news/vulnerabilities.html#CVE-2024-2511
[CVE-2024-0727]: https://www.openssl.org/news/vulnerabilities.html#CVE-2024-0727
[CVE-2023-6237]: https://www.openssl.org/news/vulnerabilities.html#CVE-2023-6237
[CVE-2023-6129]: https://www.openssl.org/news/vulnerabilities.html#CVE-2023-6129
[CVE-2023-5678]: https://www.openssl.org/news/vulnerabilities.html#CVE-2023-5678
[CVE-2023-5363]: https://www.openssl.org/news/vulnerabilities.html#CVE-2023-5363
[CVE-2023-4807]: https://www.openssl.org/news/vulnerabilities.html#CVE-2023-4807
[CVE-2023-3817]: https://www.openssl.org/news/vulnerabilities.html#CVE-2023-3817
[CVE-2023-3446]: https://www.openssl.org/news/vulnerabilities.html#CVE-2023-3446
[CVE-2023-2975]: https://www.openssl.org/news/vulnerabilities.html#CVE-2023-2975
[CVE-2023-2650]: https://www.openssl.org/news/vulnerabilities.html#CVE-2023-2650
[CVE-2023-1255]: https://www.openssl.org/news/vulnerabilities.html#CVE-2023-1255
[CVE-2023-0466]: https://www.openssl.org/news/vulnerabilities.html#CVE-2023-0466
[CVE-2023-0465]: https://www.openssl.org/news/vulnerabilities.html#CVE-2023-0465
[CVE-2023-0464]: https://www.openssl.org/news/vulnerabilities.html#CVE-2023-0464
[CVE-2023-0401]: https://www.openssl.org/news/vulnerabilities.html#CVE-2023-0401
[CVE-2023-0286]: https://www.openssl.org/news/vulnerabilities.html#CVE-2023-0286
[CVE-2023-0217]: https://www.openssl.org/news/vulnerabilities.html#CVE-2023-0217
[CVE-2023-0216]: https://www.openssl.org/news/vulnerabilities.html#CVE-2023-0216
[CVE-2023-0215]: https://www.openssl.org/news/vulnerabilities.html#CVE-2023-0215
[CVE-2022-4450]: https://www.openssl.org/news/vulnerabilities.html#CVE-2022-4450
[CVE-2022-4304]: https://www.openssl.org/news/vulnerabilities.html#CVE-2022-4304
[CVE-2022-4203]: https://www.openssl.org/news/vulnerabilities.html#CVE-2022-4203
[CVE-2022-3996]: https://www.openssl.org/news/vulnerabilities.html#CVE-2022-3996
[CVE-2022-2274]: https://www.openssl.org/news/vulnerabilities.html#CVE-2022-2274
[CVE-2022-2097]: https://www.openssl.org/news/vulnerabilities.html#CVE-2022-2097
[CVE-2020-1971]: https://www.openssl.org/news/vulnerabilities.html#CVE-2020-1971
[CVE-2020-1967]: https://www.openssl.org/news/vulnerabilities.html#CVE-2020-1967
[CVE-2019-1563]: https://www.openssl.org/news/vulnerabilities.html#CVE-2019-1563
[CVE-2019-1559]: https://www.openssl.org/news/vulnerabilities.html#CVE-2019-1559
[CVE-2019-1552]: https://www.openssl.org/news/vulnerabilities.html#CVE-2019-1552
[CVE-2019-1551]: https://www.openssl.org/news/vulnerabilities.html#CVE-2019-1551
[CVE-2019-1549]: https://www.openssl.org/news/vulnerabilities.html#CVE-2019-1549
[CVE-2019-1547]: https://www.openssl.org/news/vulnerabilities.html#CVE-2019-1547
[CVE-2019-1543]: https://www.openssl.org/news/vulnerabilities.html#CVE-2019-1543
[CVE-2018-5407]: https://www.openssl.org/news/vulnerabilities.html#CVE-2018-5407
[CVE-2018-0739]: https://www.openssl.org/news/vulnerabilities.html#CVE-2018-0739
[CVE-2018-0737]: https://www.openssl.org/news/vulnerabilities.html#CVE-2018-0737
[CVE-2018-0735]: https://www.openssl.org/news/vulnerabilities.html#CVE-2018-0735
[CVE-2018-0734]: https://www.openssl.org/news/vulnerabilities.html#CVE-2018-0734
[CVE-2018-0733]: https://www.openssl.org/news/vulnerabilities.html#CVE-2018-0733
[CVE-2018-0732]: https://www.openssl.org/news/vulnerabilities.html#CVE-2018-0732
[CVE-2017-3738]: https://www.openssl.org/news/vulnerabilities.html#CVE-2017-3738
[CVE-2017-3737]: https://www.openssl.org/news/vulnerabilities.html#CVE-2017-3737
[CVE-2017-3736]: https://www.openssl.org/news/vulnerabilities.html#CVE-2017-3736
[CVE-2017-3735]: https://www.openssl.org/news/vulnerabilities.html#CVE-2017-3735
[CVE-2017-3733]: https://www.openssl.org/news/vulnerabilities.html#CVE-2017-3733
[CVE-2017-3732]: https://www.openssl.org/news/vulnerabilities.html#CVE-2017-3732
[CVE-2017-3731]: https://www.openssl.org/news/vulnerabilities.html#CVE-2017-3731
[CVE-2017-3730]: https://www.openssl.org/news/vulnerabilities.html#CVE-2017-3730
[CVE-2016-7055]: https://www.openssl.org/news/vulnerabilities.html#CVE-2016-7055
[CVE-2016-7054]: https://www.openssl.org/news/vulnerabilities.html#CVE-2016-7054
[CVE-2016-7053]: https://www.openssl.org/news/vulnerabilities.html#CVE-2016-7053
[CVE-2016-7052]: https://www.openssl.org/news/vulnerabilities.html#CVE-2016-7052
[CVE-2016-6309]: https://www.openssl.org/news/vulnerabilities.html#CVE-2016-6309
[CVE-2016-6308]: https://www.openssl.org/news/vulnerabilities.html#CVE-2016-6308
[CVE-2016-6307]: https://www.openssl.org/news/vulnerabilities.html#CVE-2016-6307
[CVE-2016-6306]: https://www.openssl.org/news/vulnerabilities.html#CVE-2016-6306
[CVE-2016-6305]: https://www.openssl.org/news/vulnerabilities.html#CVE-2016-6305
[CVE-2016-6304]: https://www.openssl.org/news/vulnerabilities.html#CVE-2016-6304
[CVE-2016-6303]: https://www.openssl.org/news/vulnerabilities.html#CVE-2016-6303
[CVE-2016-6302]: https://www.openssl.org/news/vulnerabilities.html#CVE-2016-6302
[CVE-2016-2183]: https://www.openssl.org/news/vulnerabilities.html#CVE-2016-2183
[CVE-2016-2182]: https://www.openssl.org/news/vulnerabilities.html#CVE-2016-2182
[CVE-2016-2181]: https://www.openssl.org/news/vulnerabilities.html#CVE-2016-2181
[CVE-2016-2180]: https://www.openssl.org/news/vulnerabilities.html#CVE-2016-2180
[CVE-2016-2179]: https://www.openssl.org/news/vulnerabilities.html#CVE-2016-2179
[CVE-2016-2178]: https://www.openssl.org/news/vulnerabilities.html#CVE-2016-2178
[CVE-2016-2177]: https://www.openssl.org/news/vulnerabilities.html#CVE-2016-2177
[CVE-2016-2176]: https://www.openssl.org/news/vulnerabilities.html#CVE-2016-2176
[CVE-2016-2109]: https://www.openssl.org/news/vulnerabilities.html#CVE-2016-2109
[CVE-2016-2107]: https://www.openssl.org/news/vulnerabilities.html#CVE-2016-2107
[CVE-2016-2106]: https://www.openssl.org/news/vulnerabilities.html#CVE-2016-2106
[CVE-2016-2105]: https://www.openssl.org/news/vulnerabilities.html#CVE-2016-2105
[CVE-2016-0800]: https://www.openssl.org/news/vulnerabilities.html#CVE-2016-0800
[CVE-2016-0799]: https://www.openssl.org/news/vulnerabilities.html#CVE-2016-0799
[CVE-2016-0798]: https://www.openssl.org/news/vulnerabilities.html#CVE-2016-0798
[CVE-2016-0797]: https://www.openssl.org/news/vulnerabilities.html#CVE-2016-0797
[CVE-2016-0705]: https://www.openssl.org/news/vulnerabilities.html#CVE-2016-0705
[CVE-2016-0702]: https://www.openssl.org/news/vulnerabilities.html#CVE-2016-0702
[CVE-2016-0701]: https://www.openssl.org/news/vulnerabilities.html#CVE-2016-0701
[CVE-2015-3197]: https://www.openssl.org/news/vulnerabilities.html#CVE-2015-3197
[CVE-2015-3196]: https://www.openssl.org/news/vulnerabilities.html#CVE-2015-3196
[CVE-2015-3195]: https://www.openssl.org/news/vulnerabilities.html#CVE-2015-3195
[CVE-2015-3194]: https://www.openssl.org/news/vulnerabilities.html#CVE-2015-3194
[CVE-2015-3193]: https://www.openssl.org/news/vulnerabilities.html#CVE-2015-3193
[CVE-2015-1793]: https://www.openssl.org/news/vulnerabilities.html#CVE-2015-1793
[CVE-2015-1792]: https://www.openssl.org/news/vulnerabilities.html#CVE-2015-1792
[CVE-2015-1791]: https://www.openssl.org/news/vulnerabilities.html#CVE-2015-1791
[CVE-2015-1790]: https://www.openssl.org/news/vulnerabilities.html#CVE-2015-1790
[CVE-2015-1789]: https://www.openssl.org/news/vulnerabilities.html#CVE-2015-1789
[CVE-2015-1788]: https://www.openssl.org/news/vulnerabilities.html#CVE-2015-1788
[CVE-2015-1787]: https://www.openssl.org/news/vulnerabilities.html#CVE-2015-1787
[CVE-2015-0293]: https://www.openssl.org/news/vulnerabilities.html#CVE-2015-0293
[CVE-2015-0291]: https://www.openssl.org/news/vulnerabilities.html#CVE-2015-0291
[CVE-2015-0290]: https://www.openssl.org/news/vulnerabilities.html#CVE-2015-0290
[CVE-2015-0289]: https://www.openssl.org/news/vulnerabilities.html#CVE-2015-0289
[CVE-2015-0288]: https://www.openssl.org/news/vulnerabilities.html#CVE-2015-0288
[CVE-2015-0287]: https://www.openssl.org/news/vulnerabilities.html#CVE-2015-0287
[CVE-2015-0286]: https://www.openssl.org/news/vulnerabilities.html#CVE-2015-0286
[CVE-2015-0285]: https://www.openssl.org/news/vulnerabilities.html#CVE-2015-0285
[CVE-2015-0209]: https://www.openssl.org/news/vulnerabilities.html#CVE-2015-0209
[CVE-2015-0208]: https://www.openssl.org/news/vulnerabilities.html#CVE-2015-0208
[CVE-2015-0207]: https://www.openssl.org/news/vulnerabilities.html#CVE-2015-0207
[CVE-2015-0206]: https://www.openssl.org/news/vulnerabilities.html#CVE-2015-0206
[CVE-2015-0205]: https://www.openssl.org/news/vulnerabilities.html#CVE-2015-0205
[CVE-2015-0204]: https://www.openssl.org/news/vulnerabilities.html#CVE-2015-0204
[CVE-2014-8275]: https://www.openssl.org/news/vulnerabilities.html#CVE-2014-8275
[CVE-2014-5139]: https://www.openssl.org/news/vulnerabilities.html#CVE-2014-5139
[CVE-2014-3572]: https://www.openssl.org/news/vulnerabilities.html#CVE-2014-3572
[CVE-2014-3571]: https://www.openssl.org/news/vulnerabilities.html#CVE-2014-3571
[CVE-2014-3570]: https://www.openssl.org/news/vulnerabilities.html#CVE-2014-3570
[CVE-2014-3569]: https://www.openssl.org/news/vulnerabilities.html#CVE-2014-3569
[CVE-2014-3568]: https://www.openssl.org/news/vulnerabilities.html#CVE-2014-3568
[CVE-2014-3567]: https://www.openssl.org/news/vulnerabilities.html#CVE-2014-3567
[CVE-2014-3566]: https://www.openssl.org/news/vulnerabilities.html#CVE-2014-3566
[CVE-2014-3513]: https://www.openssl.org/news/vulnerabilities.html#CVE-2014-3513
[CVE-2014-3512]: https://www.openssl.org/news/vulnerabilities.html#CVE-2014-3512
[CVE-2014-3511]: https://www.openssl.org/news/vulnerabilities.html#CVE-2014-3511
[CVE-2014-3510]: https://www.openssl.org/news/vulnerabilities.html#CVE-2014-3510
[CVE-2014-3509]: https://www.openssl.org/news/vulnerabilities.html#CVE-2014-3509
[CVE-2014-3508]: https://www.openssl.org/news/vulnerabilities.html#CVE-2014-3508
[CVE-2014-3507]: https://www.openssl.org/news/vulnerabilities.html#CVE-2014-3507
[CVE-2014-3506]: https://www.openssl.org/news/vulnerabilities.html#CVE-2014-3506
[CVE-2014-3505]: https://www.openssl.org/news/vulnerabilities.html#CVE-2014-3505
[CVE-2014-3470]: https://www.openssl.org/news/vulnerabilities.html#CVE-2014-3470
[CVE-2014-0224]: https://www.openssl.org/news/vulnerabilities.html#CVE-2014-0224
[CVE-2014-0221]: https://www.openssl.org/news/vulnerabilities.html#CVE-2014-0221
[CVE-2014-0198]: https://www.openssl.org/news/vulnerabilities.html#CVE-2014-0198
[CVE-2014-0195]: https://www.openssl.org/news/vulnerabilities.html#CVE-2014-0195
[CVE-2014-0160]: https://www.openssl.org/news/vulnerabilities.html#CVE-2014-0160
[CVE-2014-0076]: https://www.openssl.org/news/vulnerabilities.html#CVE-2014-0076
[CVE-2013-6450]: https://www.openssl.org/news/vulnerabilities.html#CVE-2013-6450
[CVE-2013-6449]: https://www.openssl.org/news/vulnerabilities.html#CVE-2013-6449
[CVE-2013-4353]: https://www.openssl.org/news/vulnerabilities.html#CVE-2013-4353
[CVE-2013-0169]: https://www.openssl.org/news/vulnerabilities.html#CVE-2013-0169
[CVE-2013-0166]: https://www.openssl.org/news/vulnerabilities.html#CVE-2013-0166
[CVE-2012-2686]: https://www.openssl.org/news/vulnerabilities.html#CVE-2012-2686
[CVE-2012-2333]: https://www.openssl.org/news/vulnerabilities.html#CVE-2012-2333
[CVE-2012-2110]: https://www.openssl.org/news/vulnerabilities.html#CVE-2012-2110
[CVE-2012-0884]: https://www.openssl.org/news/vulnerabilities.html#CVE-2012-0884
[CVE-2012-0050]: https://www.openssl.org/news/vulnerabilities.html#CVE-2012-0050
[CVE-2012-0027]: https://www.openssl.org/news/vulnerabilities.html#CVE-2012-0027
[CVE-2011-4619]: https://www.openssl.org/news/vulnerabilities.html#CVE-2011-4619
[CVE-2011-4577]: https://www.openssl.org/news/vulnerabilities.html#CVE-2011-4577
[CVE-2011-4576]: https://www.openssl.org/news/vulnerabilities.html#CVE-2011-4576
[CVE-2011-4108]: https://www.openssl.org/news/vulnerabilities.html#CVE-2011-4108
[CVE-2011-3210]: https://www.openssl.org/news/vulnerabilities.html#CVE-2011-3210
[CVE-2011-3207]: https://www.openssl.org/news/vulnerabilities.html#CVE-2011-3207
[CVE-2011-0014]: https://www.openssl.org/news/vulnerabilities.html#CVE-2011-0014
[CVE-2010-5298]: https://www.openssl.org/news/vulnerabilities.html#CVE-2010-5298
[CVE-2010-4252]: https://www.openssl.org/news/vulnerabilities.html#CVE-2010-4252
[CVE-2010-4180]: https://www.openssl.org/news/vulnerabilities.html#CVE-2010-4180
[CVE-2010-3864]: https://www.openssl.org/news/vulnerabilities.html#CVE-2010-3864
[CVE-2010-2939]: https://www.openssl.org/news/vulnerabilities.html#CVE-2010-2939
[CVE-2010-1633]: https://www.openssl.org/news/vulnerabilities.html#CVE-2010-1633
[CVE-2010-0740]: https://www.openssl.org/news/vulnerabilities.html#CVE-2010-0740
[CVE-2010-0433]: https://www.openssl.org/news/vulnerabilities.html#CVE-2010-0433
[CVE-2009-3555]: https://www.openssl.org/news/vulnerabilities.html#CVE-2009-3555
[CVE-2009-0789]: https://www.openssl.org/news/vulnerabilities.html#CVE-2009-0789
[CVE-2009-0591]: https://www.openssl.org/news/vulnerabilities.html#CVE-2009-0591
[CVE-2009-0590]: https://www.openssl.org/news/vulnerabilities.html#CVE-2009-0590
[CVE-2008-5077]: https://www.openssl.org/news/vulnerabilities.html#CVE-2008-5077
[CVE-2006-4343]: https://www.openssl.org/news/vulnerabilities.html#CVE-2006-4343
[CVE-2006-4339]: https://www.openssl.org/news/vulnerabilities.html#CVE-2006-4339
[CVE-2006-3737]: https://www.openssl.org/news/vulnerabilities.html#CVE-2006-3737
[CVE-2006-2940]: https://www.openssl.org/news/vulnerabilities.html#CVE-2006-2940
[CVE-2006-2937]: https://www.openssl.org/news/vulnerabilities.html#CVE-2006-2937
[CVE-2005-2969]: https://www.openssl.org/news/vulnerabilities.html#CVE-2005-2969
[OpenSSL Guide]: https://www.openssl.org/docs/manmaster/man7/ossl-guide-introduction.html
[CHANGES.md]: ./CHANGES.md
[README-QUIC.md]: ./README-QUIC.md
[issue tracker]: https://github.com/openssl/openssl/issues
