ID

VAR-201609-0348

CVE

CVE-2016-6303

TITLE

OpenSSL of crypto/mdc2/mdc2dgst.c of MDC2_Update Integer overflow vulnerability in functions

DESCRIPTION

Integer overflow in the MDC2_Update function in crypto/mdc2/mdc2dgst.c in OpenSSL before 1.1.0 allows remote attackers to cause a denial of service (out-of-bounds write and application crash) or possibly have unspecified other impact via unknown vectors. OpenSSL of crypto/mdc2/mdc2dgst.c of MDC2_Update The function contains an integer overflow vulnerability. Supplementary information : CWE Vulnerability type by CWE-787: Out-of-bounds Write ( Out-of-bounds writing ) Has been identified. http://cwe.mitre.org/data/definitions/787.htmlService disruption by a third party ( Out-of-bounds writes and application crashes ) There is a possibility of being affected unspecified, such as being in a state. OpenSSL is prone to an integer-overflow vulnerability. An attacker can exploit this issue to execute arbitrary code in the context of the user running the affected application. Failed exploit attempts will likely result in denial-of-service conditions. OpenSSL versions prior to 1.1.0 are affected. -----BEGIN PGP SIGNED MESSAGE----- Hash: SHA512 APPLE-SA-2016-12-13-1 macOS 10.12.2 macOS 10.12.2 is now available and addresses the following: apache_mod_php Available for: macOS Sierra 10.12.1 Impact: A remote attacker may cause an unexpected application termination or arbitrary code execution Description: Multiple issues existed in PHP before 5.6.26. These were addressed by updating PHP to version 5.6.26. CVE-2016-7411 CVE-2016-7412 CVE-2016-7413 CVE-2016-7414 CVE-2016-7416 CVE-2016-7417 CVE-2016-7418 AppleGraphicsPowerManagement Available for: macOS Sierra 10.12.1 Impact: A local user may be able to cause a system denial of service Description: A null pointer dereference was addressed through improved input validation. CVE-2016-7609: daybreaker@Minionz working with Trend Micro's Zero Day Initiative Assets Available for: macOS Sierra 10.12.1 Impact: A local attacker may modify downloaded mobile assets Description: A permissions issue existed in mobile assets. This issue was addressed through improved access restrictions. CVE-2016-7628: an anonymous researcher Audio Available for: macOS Sierra 10.12.1 Impact: Processing a maliciously crafted file may lead to arbitrary code execution Description: A memory corruption issue was addressed through improved input validation. CVE-2016-7658: Haohao Kong of Keen Lab (@keen_lab) of Tencent CVE-2016-7659: Haohao Kong of Keen Lab (@keen_lab) of Tencent Bluetooth Available for: macOS Sierra 10.12.1, OS X El Capitan v10.11.6, and OS X Yosemite v10.10.5 Impact: An application may be able to execute arbitrary code with kernel privileges Description: A memory corruption issue was addressed through improved memory handling. CVE-2016-7596: Pekka Oikarainen, Matias Karhumaa and Marko Laakso of Synopsys Software Integrity Group Bluetooth Available for: macOS Sierra 10.12.1 Impact: An application may be able to cause a denial of service Description: A null pointer dereference was addressed through improved input validation. CVE-2016-7605: daybreaker of Minionz Bluetooth Available for: macOS Sierra 10.12.1 Impact: An application may be able to execute arbitrary code with system privileges Description: A type confusion issue was addressed through improved memory handling. CVE-2016-7617: Radu Motspan working with Trend Micro's Zero Day Initiative, Ian Beer of Google Project Zero CoreCapture Available for: macOS Sierra 10.12.1 and OS X El Capitan v10.11.6 Impact: A local user may be able to cause a system denial of service Description: A null pointer dereference was addressed through improved state management. CVE-2016-7604: daybreaker of Minionz CoreFoundation Available for: macOS Sierra 10.12.1 Impact: Processing malicious strings may lead to an unexpected application termination or arbitrary code execution Description: A memory corruption issue existed in the processing of strings. This issue was addressed through improved bounds checking. CVE-2016-7663: an anonymous researcher CoreGraphics Available for: macOS Sierra 10.12.1 Impact: Processing a maliciously crafted font file may lead to unexpected application termination Description: A null pointer dereference was addressed through improved input validation. CVE-2016-7627: TRAPMINE Inc. & Meysam Firouzi @R00tkitSMM CoreMedia External Displays Available for: macOS Sierra 10.12.1 Impact: A local application may be able to execute arbitrary code in the context of the mediaserver daemon Description: A type confusion issue was addressed through improved memory handling. CVE-2016-7655: Keen Lab working with Trend Micro's Zero Day Initiative CoreMedia Playback Available for: macOS Sierra 10.12.1 Impact: Processing a maliciously crafted .mp4 file may lead to arbitrary code execution Description: A memory corruption issue was addressed through improved memory handling. CVE-2016-7588: dragonltx of Huawei 2012 Laboratories CoreStorage Available for: macOS Sierra 10.12.1 Impact: A local user may be able to cause a system denial of service Description: A null pointer dereference was addressed through improved input validation. CVE-2016-7603: daybreaker@Minionz working with Trend Micro's Zero Day Initiative CoreText Available for: macOS Sierra 10.12.1 Impact: Processing a maliciously crafted font file may lead to arbitrary code execution Description: Multiple memory corruption issues existed in the handling of font files. These issues were addressed through improved bounds checking. CVE-2016-7595: riusksk(ae3aY=) of Tencent Security Platform Department curl Available for: macOS Sierra 10.12.1 Impact: An attacker in a privileged network position may be able to leak sensitive user information Description: Multiple issues existed in curl. These issues were addressed by updating to curl version 7.51.0. CVE-2016-5419 CVE-2016-5420 CVE-2016-5421 CVE-2016-7141 CVE-2016-7167 CVE-2016-8615 CVE-2016-8616 CVE-2016-8617 CVE-2016-8618 CVE-2016-8619 CVE-2016-8620 CVE-2016-8621 CVE-2016-8622 CVE-2016-8623 CVE-2016-8624 CVE-2016-8625 Directory Services Available for: macOS Sierra 10.12.1 Impact: A local user may be able to gain root privileges Description: A use after free issue was addressed through improved memory management. CVE-2016-7633: Ian Beer of Google Project Zero Disk Images Available for: macOS Sierra 10.12.1 Impact: An application may be able to execute arbitrary code with kernel privileges Description: A memory corruption issue was addressed through improved input validation. CVE-2016-7616: daybreaker@Minionz working with Trend Micro's Zero Day Initiative FontParser Available for: macOS Sierra 10.12.1 Impact: Processing a maliciously crafted font file may lead to arbitrary code execution Description: Multiple memory corruption issues existed in the handling of font files. These issues were addressed through improved bounds checking. CVE-2016-4691: riusksk(ae3aY=) of Tencent Security Platform Department FontParser Available for: macOS Sierra 10.12.1 Impact: Processing a maliciously crafted font file may lead to arbitrary code execution Description: A buffer overflow existed in the handling of font files. This issue was addressed through improved bounds checking. CVE-2016-4688: Simon Huang of Alipay company, thelongestusernameofall@gmail.com Foundation Available for: macOS Sierra 10.12.1 Impact: Opening a maliciously crafted .gcx file may lead to unexpected application termination or arbitrary code execution Description: A memory corruption issue was addressed through improved input validation. CVE-2016-7618: riusksk(ae3aY=) of Tencent Security Platform Department Grapher Available for: macOS Sierra 10.12.1 Impact: Opening a maliciously crafted .gcx file may lead to unexpected application termination or arbitrary code execution Description: A memory corruption issue was addressed through improved input validation. CVE-2016-7622: riusksk(ae3aY=) of Tencent Security Platform Department ICU Available for: macOS Sierra 10.12.1 Impact: Processing maliciously crafted web content may lead to arbitrary code execution Description: A memory corruption issue was addressed through improved memory handling. CVE-2016-7594: AndrA(c) Bargull ImageIO Available for: macOS Sierra 10.12.1 Impact: A remote attacker may be able to leak memory Description: An out-of-bounds read was addressed through improved bounds checking. CVE-2016-7643: Yangkang (@dnpushme) of Qihoo360 Qex Team Intel Graphics Driver Available for: macOS Sierra 10.12.1 Impact: An application may be able to execute arbitrary code with kernel privileges Description: A memory corruption issue was addressed through improved input validation. CVE-2016-7602: daybreaker@Minionz working with Trend Micro's Zero Day Initiative IOAcceleratorFamily Available for: macOS Sierra 10.12.1 Impact: A local user may be able to determine kernel memory layout Description: A shared memory issue was addressed through improved memory handling. CVE-2016-7624 : Qidan He (@flanker_hqd) from KeenLab working with Trend Micro's Zero Day Initiative IOFireWireFamily Available for: macOS Sierra 10.12.1 Impact: A local attacker may be able to read kernel memory Description: A memory corruption issue was addressed through improved memory handling. CVE-2016-7608: Brandon Azad IOHIDFamily Available for: macOS Sierra 10.12.1 Impact: An application may be able to execute arbitrary code with kernel privileges Description: A memory corruption issue was addressed through improved memory handling. CVE-2016-1823: Ian Beer of Google Project Zero IOHIDFamily Available for: macOS Sierra 10.12.1 Impact: A local application with system privileges may be able to execute arbitrary code with kernel privileges Description: A use after free issue was addressed through improved memory management. CVE-2016-7591: daybreaker of Minionz IOKit Available for: macOS Sierra 10.12.1 Impact: A local user may be able to determine kernel memory layout Description: A shared memory issue was addressed through improved memory handling. CVE-2016-7625: Qidan He (@flanker_hqd) from KeenLab working with Trend Micro's Zero Day Initiative IOKit Available for: macOS Sierra 10.12.1 Impact: An application may be able to read kernel memory Description: A memory corruption issue was addressed through improved input validation. CVE-2016-7657: Keen Lab working with Trend Micro's Zero Day Initiative IOSurface Available for: macOS Sierra 10.12.1 Impact: A local user may be able to determine kernel memory layout Description: A shared memory issue was addressed through improved memory handling. CVE-2016-7620: Qidan He (@flanker_hqd) from KeenLab working with Trend Micro's Zero Day Initiative Kernel Available for: macOS Sierra 10.12.1 Impact: An application may be able to execute arbitrary code with kernel privileges Description: Multiple memory corruption issues were addressed through improved input validation. CVE-2016-7606: @cocoahuke, Chen Qin of Topsec Alpha Team (topsec.com) CVE-2016-7612: Ian Beer of Google Project Zero Kernel Available for: macOS Sierra 10.12.1 Impact: An application may be able to read kernel memory Description: An insufficient initialization issue was addressed by properly initializing memory returned to user space. CVE-2016-7607: Brandon Azad Kernel Available for: macOS Sierra 10.12.1 Impact: A local user may be able to cause a system denial of service Description: A denial of service issue was addressed through improved memory handling. CVE-2016-7615: The UK's National Cyber Security Centre (NCSC) Kernel Available for: macOS Sierra 10.12.1 Impact: A local user may be able to cause an unexpected system termination or arbitrary code execution in the kernel Description: A use after free issue was addressed through improved memory management. CVE-2016-7621: Ian Beer of Google Project Zero Kernel Available for: macOS Sierra 10.12.1 Impact: A local user may be able to gain root privileges Description: A memory corruption issue was addressed through improved input validation. CVE-2016-7637: Ian Beer of Google Project Zero Kernel Available for: macOS Sierra 10.12.1 Impact: A local application with system privileges may be able to execute arbitrary code with kernel privileges Description: A use after free issue was addressed through improved memory management. CVE-2016-7644: Ian Beer of Google Project Zero kext tools Available for: macOS Sierra 10.12.1 Impact: An application may be able to execute arbitrary code with kernel privileges Description: A memory corruption issue was addressed through improved input validation. CVE-2016-7629: @cocoahuke libarchive Available for: macOS Sierra 10.12.1 Impact: A local attacker may be able to overwrite existing files Description: A validation issue existed in the handling of symlinks. This issue was addressed through improved validation of symlinks. CVE-2016-7619: an anonymous researcher LibreSSL Available for: macOS Sierra 10.12.1 and OS X El Capitan v10.11.6 Impact: An attacker with a privileged network position may be able to cause a denial of service Description: A denial of service issue in unbounded OCSP growth was addressed through improved memory handling. CVE-2016-6304 OpenLDAP Available for: macOS Sierra 10.12.1 Impact: An attacker may be able to exploit weaknesses in the RC4 cryptographic algorithm Description: RC4 was removed as a default cipher. CVE-2016-1777: Pepi Zawodsky OpenPAM Available for: macOS Sierra 10.12.1 Impact: A local unprivileged user may gain access to privileged applications Description: PAM authentication within sandboxed applications failed insecurely. This was addressed with improved error handling. This issue was addressed through improved input validation. CVE-2016-6303 OpenSSL Available for: macOS Sierra 10.12.1 Impact: An attacker with a privileged network position may be able to cause a denial of service Description: A denial of service issue in unbounded OCSP growth was addressed through improved memory handling. CVE-2016-6304 Power Management Available for: macOS Sierra 10.12.1 Impact: A local user may be able to gain root privileges Description: An issue in mach port name references was addressed through improved validation. CVE-2016-7661: Ian Beer of Google Project Zero Security Available for: macOS Sierra 10.12.1 Impact: An attacker may be able to exploit weaknesses in the 3DES cryptographic algorithm Description: 3DES was removed as a default cipher. CVE-2016-4693: GaA<<tan Leurent and Karthikeyan Bhargavan from INRIA Paris Security Available for: macOS Sierra 10.12.1 Impact: An attacker in a privileged network position may be able to cause a denial of service Description: A validation issue existed in the handling of OCSP responder URLs. This issue was addressed by verifying OCSP revocation status after CA validation and limiting the number of OCSP requests per certificate. CVE-2016-7636: Maksymilian Arciemowicz (cxsecurity.com) Security Available for: macOS Sierra 10.12.1 Impact: Certificates may be unexpectedly evaluated as trusted Description: A certificate evaluation issue existed in certificate validation. This issue was addressed through additional validation of certificates. CVE-2016-7662: Apple syslog Available for: macOS Sierra 10.12.1 Impact: A local user may be able to gain root privileges Description: An issue in mach port name references was addressed through improved validation. CVE-2016-7660: Ian Beer of Google Project Zero macOS 10.12.2 may be obtained from the Mac App Store or Apple's Software Downloads web site: https://www.apple.com/support/downloads/ Information will also be posted to the Apple Security Updates web site: https://support.apple.com/kb/HT201222 This message is signed with Apple's Product Security PGP key, and details are available at: https://www.apple.com/support/security/pgp/ -----BEGIN PGP SIGNATURE----- Comment: GPGTools - https://gpgtools.org iQIcBAEBCgAGBQJYT7LKAAoJEIOj74w0bLRGfKwQAN3nnwHgJNE+obIjTzpTHLlh mMQYstsO8Mcj4hjIgTCHuQr1tDldva0IZEivoYAbyXAgM9xKlIbpqBQ5TE94l3nl xTTeVqtozCCdRT36mphvwhPEp38lvclUU1IGxyvP6ieK0dHUKS8LhL9MpnaOinrX UhSiXkMs9tTZI5SgkumzBmg10oOwDnMvZDrwTcxe9vjU26V9S7+VpfsguefwDSLE fHYX4KksoEUZuDdUBrfX2+03QbqYxBjQR9IRdpcX56laq1TGUMTKwkTi9DxJlByP SJl3uvVhqWf1UkYH6x5N/gC9lXq5QO6L7W3W2rRqTtgr2UMPZsBuf0srK/lFmPvC c63thvcZyPk0cDcE7k0ZmlJx+7ihFIiPKdGwLoX5Rl6Zr29Wh9aGKhzUUYO12PUh +x18HRwXxvSv9TXAUYQu5hD48SuhUiMEBO8Qq7Z8XPFEUSJXY2AjGjai9mJYNfC4 OELKPPvYnNSd3m8YGvWY8gWgwyRP0es6U3d5rGatEpA1qcIFmUrHFhpvveL6SRSY xPQgjB/aohg/fDf3jDO1kjR7+v83B+ObbCr8MOgqGNtG3GqOimMOa8XuSMbV7+3u 0kivBY8fxYdBy0pXDdBgv+AHaTue+wgP5tQXFiAxm61Fv+uz/yvR22uaJ39P5cJf msyz+/zQNISkly6K0VBO =0QW0 -----END PGP SIGNATURE----- . Additional information can be found at https://www.openssl.org/blog/blog/2016/06/27/undefined-pointer-arithmetic/ CVE-2016-2178 Cesar Pereida, Billy Brumley and Yuval Yarom discovered a timing leak in the DSA code. CVE-2016-2179 / CVE-2016-2181 Quan Luo and the OCAP audit team discovered denial of service vulnerabilities in DTLS. For the stable distribution (jessie), these problems have been fixed in version 1.0.1t-1+deb8u4. For the unstable distribution (sid), these problems will be fixed soon. ========================================================================== Ubuntu Security Notice USN-3087-2 September 23, 2016 openssl regression ========================================================================== A security issue affects these releases of Ubuntu and its derivatives: - Ubuntu 16.04 LTS - Ubuntu 14.04 LTS - Ubuntu 12.04 LTS Summary: USN-3087-1 introduced a regression in OpenSSL. Software Description: - openssl: Secure Socket Layer (SSL) cryptographic library and tools Details: USN-3087-1 fixed vulnerabilities in OpenSSL. The fix for CVE-2016-2182 was incomplete and caused a regression when parsing certificates. This update fixes the problem. We apologize for the inconvenience. (CVE-2016-6304) Guido Vranken discovered that OpenSSL used undefined behaviour when performing pointer arithmetic. (CVE-2016-2178) Quan Luo discovered that OpenSSL did not properly restrict the lifetime of queue entries in the DTLS implementation. (CVE-2016-2179) Shi Lei discovered that OpenSSL incorrectly handled memory in the TS_OBJ_print_bio() function. (CVE-2016-2180) It was discovered that the OpenSSL incorrectly handled the DTLS anti-replay feature. (CVE-2016-2181) Shi Lei discovered that OpenSSL incorrectly validated division results. (CVE-2016-2182) Karthik Bhargavan and Gaetan Leurent discovered that the DES and Triple DES ciphers were vulnerable to birthday attacks. A remote attacker could possibly use this flaw to obtain clear text data from long encrypted sessions. This update moves DES from the HIGH cipher list to MEDIUM. (CVE-2016-2183) Shi Lei discovered that OpenSSL incorrectly handled certain ticket lengths. (CVE-2016-6302) Shi Lei discovered that OpenSSL incorrectly handled memory in the MDC2_Update() function. (CVE-2016-6303) Shi Lei discovered that OpenSSL incorrectly performed certain message length checks. (CVE-2016-6306) Update instructions: The problem can be corrected by updating your system to the following package versions: Ubuntu 16.04 LTS: libssl1.0.0 1.0.2g-1ubuntu4.5 Ubuntu 14.04 LTS: libssl1.0.0 1.0.1f-1ubuntu2.21 Ubuntu 12.04 LTS: libssl1.0.0 1.0.1-4ubuntu5.38 After a standard system update you need to reboot your computer to make all the necessary changes. References: http://www.ubuntu.com/usn/usn-3087-2 http://www.ubuntu.com/usn/usn-3087-1 https://launchpad.net/bugs/1626883 Package Information: https://launchpad.net/ubuntu/+source/openssl/1.0.2g-1ubuntu4.5 https://launchpad.net/ubuntu/+source/openssl/1.0.1f-1ubuntu2.21 https://launchpad.net/ubuntu/+source/openssl/1.0.1-4ubuntu5.38 . OpenSSL Security Advisory [22 Sep 2016] ======================================== OCSP Status Request extension unbounded memory growth (CVE-2016-6304) ===================================================================== Severity: High A malicious client can send an excessively large OCSP Status Request extension. If that client continually requests renegotiation, sending a large OCSP Status Request extension each time, then there will be unbounded memory growth on the server. This will eventually lead to a Denial Of Service attack through memory exhaustion. Servers with a default configuration are vulnerable even if they do not support OCSP. Builds using the "no-ocsp" build time option are not affected. Servers using OpenSSL versions prior to 1.0.1g are not vulnerable in a default configuration, instead only if an application explicitly enables OCSP stapling support. OpenSSL 1.1.0 users should upgrade to 1.1.0a OpenSSL 1.0.2 users should upgrade to 1.0.2i OpenSSL 1.0.1 users should upgrade to 1.0.1u This issue was reported to OpenSSL on 29th August 2016 by Shi Lei (Gear Team, Qihoo 360 Inc.). The fix was developed by Matt Caswell of the OpenSSL development team. SSL_peek() hang on empty record (CVE-2016-6305) =============================================== Severity: Moderate OpenSSL 1.1.0 SSL/TLS will hang during a call to SSL_peek() if the peer sends an empty record. This could be exploited by a malicious peer in a Denial Of Service attack. OpenSSL 1.1.0 users should upgrade to 1.1.0a This issue was reported to OpenSSL on 10th September 2016 by Alex Gaynor. The fix was developed by Matt Caswell of the OpenSSL development team. SWEET32 Mitigation (CVE-2016-2183) ================================== Severity: Low SWEET32 (https://sweet32.info) is an attack on older block cipher algorithms that use a block size of 64 bits. In mitigation for the SWEET32 attack DES based ciphersuites have been moved from the HIGH cipherstring group to MEDIUM in OpenSSL 1.0.1 and OpenSSL 1.0.2. OpenSSL 1.1.0 since release has had these ciphersuites disabled by default. OpenSSL 1.0.2 users should upgrade to 1.0.2i OpenSSL 1.0.1 users should upgrade to 1.0.1u This issue was reported to OpenSSL on 16th August 2016 by Karthikeyan Bhargavan and Gaetan Leurent (INRIA). The fix was developed by Rich Salz of the OpenSSL development team. OOB write in MDC2_Update() (CVE-2016-6303) ========================================== Severity: Low An overflow can occur in MDC2_Update() either if called directly or through the EVP_DigestUpdate() function using MDC2. 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. The amount of data needed is comparable to SIZE_MAX which is impractical on most platforms. OpenSSL 1.0.2 users should upgrade to 1.0.2i OpenSSL 1.0.1 users should upgrade to 1.0.1u This issue was reported to OpenSSL on 11th August 2016 by Shi Lei (Gear Team, Qihoo 360 Inc.). The fix was developed by Stephen Henson of the OpenSSL development team. Malformed SHA512 ticket DoS (CVE-2016-6302) =========================================== Severity: Low If a server uses SHA512 for TLS session ticket HMAC it is vulnerable to a DoS attack where a malformed ticket will result in an OOB read which will ultimately crash. The use of SHA512 in TLS session tickets is comparatively rare as it requires a custom server callback and ticket lookup mechanism. OpenSSL 1.0.2 users should upgrade to 1.0.2i OpenSSL 1.0.1 users should upgrade to 1.0.1u This issue was reported to OpenSSL on 19th August 2016 by Shi Lei (Gear Team, Qihoo 360 Inc.). The fix was developed by Stephen Henson of the OpenSSL development team. OOB write in BN_bn2dec() (CVE-2016-2182) ======================================== Severity: Low The function BN_bn2dec() does not check the return value of BN_div_word(). This can cause an OOB write if an application uses this function with an overly large BIGNUM. This could be a problem if an overly large certificate or CRL is printed out from an untrusted source. TLS is not affected because record limits will reject an oversized certificate before it is parsed. OpenSSL 1.0.2 users should upgrade to 1.0.2i OpenSSL 1.0.1 users should upgrade to 1.0.1u This issue was reported to OpenSSL on 2nd August 2016 by Shi Lei (Gear Team, Qihoo 360 Inc.). The fix was developed by Stephen Henson of the OpenSSL development team. OOB read in TS_OBJ_print_bio() (CVE-2016-2180) ============================================== Severity: Low The function TS_OBJ_print_bio() misuses OBJ_obj2txt(): the return value is the total length the OID text representation would use and not the amount of data written. This will result in OOB reads when large OIDs are presented. OpenSSL 1.0.2 users should upgrade to 1.0.2i OpenSSL 1.0.1 users should upgrade to 1.0.1u This issue was reported to OpenSSL on 21st July 2016 by Shi Lei (Gear Team, Qihoo 360 Inc.). The fix was developed by Stephen Henson of the OpenSSL development team. Pointer arithmetic undefined behaviour (CVE-2016-2177) ====================================================== Severity: Low Avoid some undefined pointer arithmetic A common idiom in the codebase is to check limits in the following manner: "p + len > limit" Where "p" points to some malloc'd data of SIZE bytes and limit == p + SIZE "len" here could be from some externally supplied data (e.g. from a TLS message). The rules of C pointer arithmetic are such that "p + len" is only well defined where len <= SIZE. Therefore the above idiom is actually undefined behaviour. For example this could cause problems if some malloc implementation provides an address for "p" such that "p + len" actually overflows for values of len that are too big and therefore p + len < limit. OpenSSL 1.0.2 users should upgrade to 1.0.2i OpenSSL 1.0.1 users should upgrade to 1.0.1u This issue was reported to OpenSSL on 4th May 2016 by Guido Vranken. The fix was developed by Matt Caswell of the OpenSSL development team. Constant time flag not preserved in DSA signing (CVE-2016-2178) =============================================================== Severity: Low Operations in the DSA signing algorithm should run in constant time in order to avoid side channel attacks. A flaw in the OpenSSL DSA implementation means that a non-constant time codepath is followed for certain operations. This has been demonstrated through a cache-timing attack to be sufficient for an attacker to recover the private DSA key. OpenSSL 1.0.2 users should upgrade to 1.0.2i OpenSSL 1.0.1 users should upgrade to 1.0.1u This issue was reported to OpenSSL on 23rd May 2016 by César Pereida (Aalto University), Billy Brumley (Tampere University of Technology), and Yuval Yarom (The University of Adelaide and NICTA). The fix was developed by César Pereida. DTLS buffered message DoS (CVE-2016-2179) ========================================= Severity: Low In a DTLS connection where handshake messages are delivered out-of-order those messages that OpenSSL is not yet ready to process will be buffered for later use. Under certain circumstances, a flaw in the logic means that those messages do not get removed from the buffer even though the handshake has been completed. An attacker could force up to approx. 15 messages to remain in the buffer when they are no longer required. These messages will be cleared when the DTLS connection is closed. The default maximum size for a message is 100k. Therefore the attacker could force an additional 1500k to be consumed per connection. By opening many simulataneous connections an attacker could cause a DoS attack through memory exhaustion. OpenSSL 1.0.2 DTLS users should upgrade to 1.0.2i OpenSSL 1.0.1 DTLS users should upgrade to 1.0.1u This issue was reported to OpenSSL on 22nd June 2016 by Quan Luo. The fix was developed by Matt Caswell of the OpenSSL development team. DTLS replay protection DoS (CVE-2016-2181) ========================================== Severity: Low A flaw in the DTLS replay attack protection mechanism means that records that arrive for future epochs update the replay protection "window" before the MAC for the record has been validated. This could be exploited by an attacker by sending a record for the next epoch (which does not have to decrypt or have a valid MAC), with a very large sequence number. This means that all subsequent legitimate packets are dropped causing a denial of service for a specific DTLS connection. OpenSSL 1.0.2 DTLS users should upgrade to 1.0.2i OpenSSL 1.0.1 DTLS users should upgrade to 1.0.1u This issue was reported to OpenSSL on 21st November 2015 by the OCAP audit team. The fix was developed by Matt Caswell of the OpenSSL development team. Certificate message OOB reads (CVE-2016-6306) ============================================= Severity: Low In OpenSSL 1.0.2 and earlier some missing message length checks can result in OOB reads of up to 2 bytes beyond an allocated buffer. There is a theoretical DoS risk but this has not been observed in practice on common platforms. The messages affected are client certificate, client certificate request and server certificate. As a result the attack can only be performed against a client or a server which enables client authentication. OpenSSL 1.0.2 users should upgrade to 1.0.2i OpenSSL 1.0.1 users should upgrade to 1.0.1u This issue was reported to OpenSSL on 22nd August 2016 by Shi Lei (Gear Team, Qihoo 360 Inc.). The fix was developed by Stephen Henson of the OpenSSL development team. Excessive allocation of memory in tls_get_message_header() (CVE-2016-6307) ========================================================================== Severity: Low A TLS message includes 3 bytes for its length in the header for the message. This would allow for messages up to 16Mb in length. Messages of this length are excessive and OpenSSL includes a check to ensure that a peer is sending reasonably sized messages in order to avoid too much memory being consumed to service a connection. A flaw in the logic of version 1.1.0 means that memory for the message is allocated too early, prior to the excessive message length check. Due to way memory is allocated in OpenSSL this could mean an attacker could force up to 21Mb to be allocated to service a connection. This could lead to a Denial of Service through memory exhaustion. However, the excessive message length check still takes place, and this would cause the connection to immediately fail. Assuming that the application calls SSL_free() on the failed conneciton in a timely manner then the 21Mb of allocated memory will then be immediately freed again. Therefore the excessive memory allocation will be transitory in nature. This then means that there is only a security impact if: 1) The application does not call SSL_free() in a timely manner in the event that the connection fails or 2) The application is working in a constrained environment where there is very little free memory or 3) The attacker initiates multiple connection attempts such that there are multiple connections in a state where memory has been allocated for the connection; SSL_free() has not yet been called; and there is insufficient memory to service the multiple requests. Except in the instance of (1) above any Denial Of Service is likely to be transitory because as soon as the connection fails the memory is subsequently freed again in the SSL_free() call. However there is an increased risk during this period of application crashes due to the lack of memory - which would then mean a more serious Denial of Service. This issue does not affect DTLS users. OpenSSL 1.1.0 TLS users should upgrade to 1.1.0a This issue was reported to OpenSSL on 18th September 2016 by Shi Lei (Gear Team, Qihoo 360 Inc.). The fix was developed by Matt Caswell of the OpenSSL development team. Excessive allocation of memory in dtls1_preprocess_fragment() (CVE-2016-6308) ============================================================================= Severity: Low This issue is very similar to CVE-2016-6307. The underlying defect is different but the security analysis and impacts are the same except that it impacts DTLS. A DTLS message includes 3 bytes for its length in the header for the message. This would allow for messages up to 16Mb in length. Messages of this length are excessive and OpenSSL includes a check to ensure that a peer is sending reasonably sized messages in order to avoid too much memory being consumed to service a connection. A flaw in the logic of version 1.1.0 means that memory for the message is allocated too early, prior to the excessive message length check. Due to way memory is allocated in OpenSSL this could mean an attacker could force up to 21Mb to be allocated to service a connection. This could lead to a Denial of Service through memory exhaustion. However, the excessive message length check still takes place, and this would cause the connection to immediately fail. Assuming that the application calls SSL_free() on the failed conneciton in a timely manner then the 21Mb of allocated memory will then be immediately freed again. Therefore the excessive memory allocation will be transitory in nature. This then means that there is only a security impact if: 1) The application does not call SSL_free() in a timely manner in the event that the connection fails or 2) The application is working in a constrained environment where there is very little free memory or 3) The attacker initiates multiple connection attempts such that there are multiple connections in a state where memory has been allocated for the connection; SSL_free() has not yet been called; and there is insufficient memory to service the multiple requests. Except in the instance of (1) above any Denial Of Service is likely to be transitory because as soon as the connection fails the memory is subsequently freed again in the SSL_free() call. However there is an increased risk during this period of application crashes due to the lack of memory - which would then mean a more serious Denial of Service. This issue does not affect TLS users. OpenSSL 1.1.0 DTLS users should upgrade to 1.1.0a This issue was reported to OpenSSL on 18th September 2016 by Shi Lei (Gear Team, Qihoo 360 Inc.). 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/policies/releasestrat.html), support for OpenSSL version 1.0.1 will cease on 31st December 2016. No security updates for that version will be provided after that date. Users of 1.0.1 are advised to upgrade. Support for versions 0.9.8 and 1.0.0 ended on 31st December 2015. Those versions are no longer receiving security updates. References ========== URL for this Security Advisory: https://www.openssl.org/news/secadv/20160922.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/policies/secpolicy.html

AFFECTED PRODUCTS