diff --git a/CHANGES b/CHANGES index d4e9887370..21f2a37fe1 100644 --- a/CHANGES +++ b/CHANGES @@ -4,6 +4,93 @@ Changes between 1.0.1s and 1.0.1t [xx XXX xxxx] + *) Prevent padding oracle in AES-NI CBC MAC check + + A MITM attacker can use a padding oracle attack to decrypt traffic + when the connection uses an AES CBC cipher and the server support + AES-NI. + + This issue was introduced as part of the fix for Lucky 13 padding + attack (CVE-2013-0169). The padding check was rewritten to be in + constant time by making sure that always the same bytes are read and + compared against either the MAC or padding bytes. But it no longer + checked that there was enough data to have both the MAC and padding + bytes. + + This issue was reported by Juraj Somorovsky using TLS-Attacker. + (CVE-2016-2107) + [Kurt Roeckx] + + *) Fix EVP_EncodeUpdate overflow + + An overflow can occur in the EVP_EncodeUpdate() function which is used for + Base64 encoding of binary data. If an attacker is able to supply very large + amounts of input data then a length check can overflow resulting in a heap + corruption. + + Internally to OpenSSL the EVP_EncodeUpdate() function is primarly used by + the PEM_write_bio* family of functions. These are mainly used within the + OpenSSL command line applications, so any application which processes data + from an untrusted source and outputs it as a PEM file should be considered + vulnerable to this issue. User applications that call these APIs directly + with large amounts of untrusted data may also be vulnerable. + + This issue was reported by Guido Vranken. + (CVE-2016-2105) + [Matt Caswell] + + *) Fix EVP_EncryptUpdate overflow + + An overflow can occur in the EVP_EncryptUpdate() function. If an attacker + is able to supply very large amounts of input data after a previous call to + EVP_EncryptUpdate() with a partial block then a length check can overflow + resulting in a heap corruption. Following an analysis of all OpenSSL + internal usage of the EVP_EncryptUpdate() function all usage is one of two + forms. The first form is where the EVP_EncryptUpdate() call is known to be + the first called function after an EVP_EncryptInit(), and therefore that + specific call must be safe. The second form is where the length passed to + EVP_EncryptUpdate() can be seen from the code to be some small value and + therefore there is no possibility of an overflow. Since all instances are + one of these two forms, it is believed that there can be no overflows in + internal code due to this problem. It should be noted that + EVP_DecryptUpdate() can call EVP_EncryptUpdate() in certain code paths. + Also EVP_CipherUpdate() is a synonym for EVP_EncryptUpdate(). All instances + of these calls have also been analysed too and it is believed there are no + instances in internal usage where an overflow could occur. + + This issue was reported by Guido Vranken. + (CVE-2016-2106) + [Matt Caswell] + + *) Prevent ASN.1 BIO excessive memory allocation + + When ASN.1 data is read from a BIO using functions such as d2i_CMS_bio() + a short invalid encoding can casuse allocation of large amounts of memory + potentially consuming excessive resources or exhausting memory. + + Any application parsing untrusted data through d2i BIO functions is + affected. The memory based functions such as d2i_X509() are *not* affected. + Since the memory based functions are used by the TLS library, TLS + applications are not affected. + + This issue was reported by Brian Carpenter. + (CVE-2016-2109) + [Stephen Henson] + + *) EBCDIC overread + + ASN1 Strings that are over 1024 bytes can cause an overread in applications + using the X509_NAME_oneline() function on EBCDIC systems. This could result + in arbitrary stack data being returned in the buffer. + + This issue was reported by Guido Vranken. + (CVE-2016-2176) + [Matt Caswell] + + *) Modify behavior of ALPN to invoke callback after SNI/servername + callback, such that updates to the SSL_CTX affect ALPN. + [Todd Short] + *) Remove LOW from the DEFAULT cipher list. This removes singles DES from the default. [Kurt Roeckx] diff --git a/NEWS b/NEWS index 428981417b..71f5e57252 100644 --- a/NEWS +++ b/NEWS @@ -7,7 +7,16 @@ Major changes between OpenSSL 1.0.1s and OpenSSL 1.0.1t [under development] - o + o Prevent padding oracle in AES-NI CBC MAC check (CVE-2016-2107) + o Fix EVP_EncodeUpdate overflow (CVE-2016-2105) + o Fix EVP_EncryptUpdate overflow (CVE-2016-2106) + o Prevent ASN.1 BIO excessive memory allocation (CVE-2016-2109) + o EBCDIC overread (CVE-2016-2176) + o Modify behavior of ALPN to invoke callback after SNI/servername + callback, such that updates to the SSL_CTX affect ALPN. + o Remove LOW from the DEFAULT cipher list. This removes singles DES from + the default. + o 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]