OpenSSL Security Advisory [08 Jan 2015] ======================================= DTLS segmentation fault in dtls1_get_record (CVE-2014-3571) =========================================================== Severity: Moderate A carefully crafted DTLS message can cause a segmentation fault in OpenSSL due to a NULL pointer dereference. This could lead to a Denial Of Service attack. This issue affects all current OpenSSL versions: 1.0.1, 1.0.0 and 0.9.8. OpenSSL 1.0.1 DTLS users should upgrade to 1.0.1k. OpenSSL 1.0.0 DTLS users should upgrade to 1.0.0p. OpenSSL 0.9.8 DTLS users should upgrade to 0.9.8zd. This issue was reported to OpenSSL on 22nd October 2014 by Markus Stenberg of Cisco Systems, Inc. The fix was developed by Stephen Henson of the OpenSSL core team. DTLS memory leak in dtls1_buffer_record (CVE-2015-0206) ======================================================= Severity: Moderate A memory leak can occur in the dtls1_buffer_record function under certain conditions. In particular this could occur if an attacker sent repeated DTLS records with the same sequence number but for the next epoch. The memory leak could be exploited by an attacker in a Denial of Service attack through memory exhaustion. This issue affects OpenSSL versions: 1.0.1 and 1.0.0. OpenSSL 1.0.1 DTLS users should upgrade to 1.0.1k. OpenSSL 1.0.0 DTLS users should upgrade to 1.0.0p. This issue was reported to OpenSSL on 7th January 2015 by Chris Mueller who also provided an initial patch. Further analysis was performed by Matt Caswell of the OpenSSL development team, who also developed the final patch. no-ssl3 configuration sets method to NULL (CVE-2014-3569) ========================================================= Severity: Low When openssl is built with the no-ssl3 option and a SSL v3 ClientHello is received the ssl method would be set to NULL which could later result in a NULL pointer dereference. This issue affects all current OpenSSL versions: 1.0.1, 1.0.0 and 0.9.8. OpenSSL 1.0.1 users should upgrade to 1.0.1k. OpenSSL 1.0.0 users should upgrade to 1.0.0p. OpenSSL 0.9.8 users should upgrade to 0.9.8zd. This issue was reported to OpenSSL on 17th October 2014 by Frank Schmirler. The fix was developed by Kurt Roeckx. ECDHE silently downgrades to ECDH [Client] (CVE-2014-3572) ========================================================== Severity: Low An OpenSSL client will accept a handshake using an ephemeral ECDH ciphersuite using an ECDSA certificate if the server key exchange message is omitted. This effectively removes forward secrecy from the ciphersuite. This issue affects all current OpenSSL versions: 1.0.1, 1.0.0 and 0.9.8. OpenSSL 1.0.1 users should upgrade to 1.0.1k. OpenSSL 1.0.0 users should upgrade to 1.0.0p. OpenSSL 0.9.8 users should upgrade to 0.9.8zd. This issue was reported to OpenSSL on 22nd October 2014 by Karthikeyan Bhargavan of the PROSECCO team at INRIA. The fix was developed by Stephen Henson of the OpenSSL core team. RSA silently downgrades to EXPORT_RSA [Client] (CVE-2015-0204) ============================================================== Severity: Low An OpenSSL client will accept the use of an RSA temporary key in a non-export RSA key exchange ciphersuite. A server could present a weak temporary key and downgrade the security of the session. This issue affects all current OpenSSL versions: 1.0.1, 1.0.0 and 0.9.8. OpenSSL 1.0.1 users should upgrade to 1.0.1k. OpenSSL 1.0.0 users should upgrade to 1.0.0p. OpenSSL 0.9.8 users should upgrade to 0.9.8zd. This issue was reported to OpenSSL on 22nd October 2014 by Karthikeyan Bhargavan of the PROSECCO team at INRIA. The fix was developed by Stephen Henson of the OpenSSL core team. DH client certificates accepted without verification [Server] (CVE-2015-0205) ============================================================================= Severity: Low An OpenSSL server will accept a DH certificate for client authentication without the certificate verify message. This effectively allows a client to authenticate without the use of a private key. This only affects servers which trust a client certificate authority which issues certificates containing DH keys: these are extremely rare and hardly ever encountered. This issue affects OpenSSL versions: 1.0.1 and 1.0.0. OpenSSL 1.0.1 users should upgrade to 1.0.1k. OpenSSL 1.0.0 users should upgrade to 1.0.0p. This issue was reported to OpenSSL on 22nd October 2014 by Karthikeyan Bhargavan of the PROSECCO team at INRIA. The fix was developed by Stephen Henson of the OpenSSL core team. Certificate fingerprints can be modified (CVE-2014-8275) ======================================================== Severity: Low OpenSSL accepts several non-DER-variations of certificate signature algorithm and signature encodings. OpenSSL also does not enforce a match between the signature algorithm between the signed and unsigned portions of the certificate. By modifying the contents of the signature algorithm or the encoding of the signature, it is possible to change the certificate's fingerprint. This does not allow an attacker to forge certificates, and does not affect certificate verification or OpenSSL servers/clients in any other way. It also does not affect common revocation mechanisms. Only custom applications that rely on the uniqueness of the fingerprint (e.g. certificate blacklists) may be affected. This issue affects all current OpenSSL versions: 1.0.1, 1.0.0 and 0.9.8. OpenSSL 1.0.1 users should upgrade to 1.0.1k. OpenSSL 1.0.0 users should upgrade to 1.0.0p. OpenSSL 0.9.8 users should upgrade to 0.9.8zd. One variant of this issue was discovered by Antti Karjalainen and Tuomo Untinen from the Codenomicon CROSS program and reported to OpenSSL on 1st December 2014 by NCSC-FI Vulnerability Co-ordination. Another variant was independently reported to OpenSSL on 12th December 2014 by Konrad Kraszewski from Google. Further analysis was conducted and fixes were developed by Stephen Henson of the OpenSSL core team. Bignum squaring may produce incorrect results (CVE-2014-3570) ============================================================= Severity: Low Bignum squaring (BN_sqr) may produce incorrect results on some platforms, including x86_64. This bug occurs at random with a very low probability, and is not known to be exploitable in any way, though its exact impact is difficult to determine. The following has been determined: *) The probability of BN_sqr producing an incorrect result at random is very low: 1/2^64 on the single affected 32-bit platform (MIPS) and 1/2^128 on affected 64-bit platforms. *) On most platforms, RSA follows a different code path and RSA operations are not affected at all. For the remaining platforms (e.g. OpenSSL built without assembly support), pre-existing countermeasures thwart bug attacks [1]. *) Static ECDH is theoretically affected: it is possible to construct elliptic curve points that would falsely appear to be on the given curve. However, there is no known computationally feasible way to construct such points with low order, and so the security of static ECDH private keys is believed to be unaffected. *) Other routines known to be theoretically affected are modular exponentiation, primality testing, DSA, RSA blinding, JPAKE and SRP. No exploits are known and straightforward bug attacks fail - either the attacker cannot control when the bug triggers, or no private key material is involved. This issue affects all current OpenSSL versions: 1.0.1, 1.0.0 and 0.9.8. OpenSSL 1.0.1 users should upgrade to 1.0.1k. OpenSSL 1.0.0 users should upgrade to 1.0.0p. OpenSSL 0.9.8 users should upgrade to 0.9.8zd. This issue was reported to OpenSSL on 2nd November 2014 by Pieter Wuille (Blockstream) who also suggested an initial fix. Further analysis was conducted by the OpenSSL development team and Adam Langley of Google. The final fix was developed by Andy Polyakov of the OpenSSL core team. [1] http://css.csail.mit.edu/6.858/2013/readings/rsa-bug-attacks.pdf 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 releases will be provided after that date. Users of these releases are advised to upgrade. References ========== URL for this Security Advisory: https://www.openssl.org/news/secadv_20150108.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