OpenSSL Security Advisory [3 Dec 2015] - Updated [4 Dec 2015] ============================================================= [Updated 4 Dec 2015]: This advisory has been updated to include the details of CVE-2015-1794, a Low severity issue affecting OpenSSL 1.0.2 which had a fix included in the released packages but was missed from the advisory text. NOTE: WE ANTICIPATE THAT 1.0.0t AND 0.9.8zh WILL BE THE LAST RELEASES FOR THE 0.9.8 AND 1.0.0 VERSIONS AND THAT NO MORE SECURITY FIXES WILL BE PROVIDED (AS PER PREVIOUS ANNOUNCEMENTS). USERS ARE ADVISED TO UPGRADE TO LATER VERSIONS. BN_mod_exp may produce incorrect results on x86_64 (CVE-2015-3193) ================================================================== Severity: Moderate There is a carry propagating bug in the x86_64 Montgomery squaring procedure. No EC algorithms are affected. Analysis suggests that attacks against RSA and DSA as a result of this defect would be very difficult to perform and are not believed likely. Attacks against DH are considered just feasible (although very difficult) because most of the work necessary to deduce information about a private key may be performed offline. The amount of resources required for such an attack would be very significant and likely only accessible to a limited number of attackers. An attacker would additionally need online access to an unpatched system using the target private key in a scenario with persistent DH parameters and a private key that is shared between multiple clients. For example this can occur by default in OpenSSL DHE based SSL/TLS ciphersuites. This issue affects OpenSSL version 1.0.2. OpenSSL 1.0.2 users should upgrade to 1.0.2e This issue was reported to OpenSSL on August 13 2015 by Hanno Böck. The fix was developed by Andy Polyakov of the OpenSSL development team. Certificate verify crash with missing PSS parameter (CVE-2015-3194) =================================================================== Severity: Moderate The signature verification routines will crash with a NULL pointer dereference if presented with an ASN.1 signature using the RSA PSS algorithm and absent mask generation function parameter. Since these routines are used to verify certificate signature algorithms this can be used to crash any certificate verification operation and exploited in a DoS attack. Any application which performs certificate verification is vulnerable including OpenSSL clients and servers which enable client authentication. This issue affects OpenSSL versions 1.0.2 and 1.0.1. OpenSSL 1.0.2 users should upgrade to 1.0.2e OpenSSL 1.0.1 users should upgrade to 1.0.1q This issue was reported to OpenSSL on August 27 2015 by Loïc Jonas Etienne (Qnective AG). The fix was developed by Dr. Stephen Henson of the OpenSSL development team. X509_ATTRIBUTE memory leak (CVE-2015-3195) ========================================== Severity: Moderate When presented with a malformed X509_ATTRIBUTE structure OpenSSL will leak memory. This structure is used by the PKCS#7 and CMS routines so any application which reads PKCS#7 or CMS data from untrusted sources is affected. SSL/TLS is not affected. This issue affects OpenSSL versions 1.0.2 and 1.0.1, 1.0.0 and 0.9.8. OpenSSL 1.0.2 users should upgrade to 1.0.2e OpenSSL 1.0.1 users should upgrade to 1.0.1q OpenSSL 1.0.0 users should upgrade to 1.0.0t OpenSSL 0.9.8 users should upgrade to 0.9.8zh This issue was reported to OpenSSL on November 9 2015 by Adam Langley (Google/BoringSSL) using libFuzzer. The fix was developed by Dr. Stephen Henson of the OpenSSL development team. Race condition handling PSK identify hint (CVE-2015-3196) ========================================================= Severity: Low If PSK identity hints are received by a multi-threaded client then the values are wrongly updated in the parent SSL_CTX structure. This can result in a race condition potentially leading to a double free of the identify hint data. This issue was fixed in OpenSSL 1.0.2d and 1.0.1p but has not been previously listed in an OpenSSL security advisory. This issue also affects OpenSSL 1.0.0 and has not been previously fixed in an OpenSSL 1.0.0 release. OpenSSL 1.0.2 users should upgrade to 1.0.2d OpenSSL 1.0.1 users should upgrade to 1.0.1p OpenSSL 1.0.0 users should upgrade to 1.0.0t The fix for this issue can be identified in the OpenSSL git repository by commit ids 3c66a669dfc7 (1.0.2), d6be3124f228 (1.0.1) and 1392c238657e (1.0.0). The fix was developed by Dr. Stephen Henson of the OpenSSL development team. Anon DH ServerKeyExchange with 0 p parameter (CVE-2015-1794) ============================================================ Severity: Low If a client receives a ServerKeyExchange for an anonymous DH ciphersuite with the value of p set to 0 then a seg fault can occur leading to a possible denial of service attack. This issue affects OpenSSL version 1.0.2. OpenSSL 1.0.2 users should upgrade to 1.0.2e This issue was reported to OpenSSL on August 3 2015 by Guy Leaver (Cisco). The fix was developed by Matt Caswell of the OpenSSL development team. Note ==== As per our previous announcements and our Release Strategy (https://www.openssl.org/about/releasestrat.html), support for OpenSSL versions 1.0.0 and 0.9.8 will cease on 31st December 2015. No security updates for these versions will be provided after that date. In the absence of significant security issues being identified prior to that date, the 1.0.0t and 0.9.8zh releases will be the last for those versions. Users of these versions are advised to upgrade. References ========== URL for this Security Advisory: https://www.openssl.org/news/secadv/20151203.txt Note: the online version of the advisory may be updated with additional details over time. For details of OpenSSL severity classifications please see: https://www.openssl.org/about/secpolicy.html