Several security issues were fixed in OpenSSL.
Shi Lei discovered that OpenSSL incorrectly handled the OCSP Status Request extension. A remote attacker could possibly use this issue to cause memory consumption, resulting in a denial of service. (CVE-2016-6304)
22 September 2016
A security issue affects these releases of Ubuntu and its derivatives:
Several security issues were fixed in OpenSSL.
Shi Lei discovered that OpenSSL incorrectly handled the OCSP Status Request extension. A remote attacker could possibly use this issue to cause memory consumption, resulting in a denial of service. (CVE-2016-6304)
Guido Vranken discovered that OpenSSL used undefined behaviour when performing pointer arithmetic. A remote attacker could possibly use this issue to cause OpenSSL to crash, resulting in a denial of service. This issue has only been addressed in Ubuntu 16.04 LTS in this update. (CVE-2016-2177)
César Pereida, Billy Brumley, and Yuval Yarom discovered that OpenSSL did not properly use constant-time operations when performing DSA signing. A remote attacker could possibly use this issue to perform a cache-timing attack and recover private DSA keys. (CVE-2016-2178)
Quan Luo discovered that OpenSSL did not properly restrict the lifetime of queue entries in the DTLS implementation. A remote attacker could possibly use this issue to consume memory, resulting in a denial of service. (CVE-2016-2179)
Shi Lei discovered that OpenSSL incorrectly handled memory in the TS_OBJ_print_bio() function. A remote attacker could possibly use this issue to cause a denial of service. (CVE-2016-2180)
It was discovered that the OpenSSL incorrectly handled the DTLS anti-replay feature. A remote attacker could possibly use this issue to cause a denial of service. (CVE-2016-2181)
Shi Lei discovered that OpenSSL incorrectly validated division results. A remote attacker could possibly use this issue to cause a denial of service. (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. A remote attacker could use this issue to cause a denial of service. (CVE-2016-6302)
Shi Lei discovered that OpenSSL incorrectly handled memory in the MDC2_Update() function. A remote attacker could possibly use this issue to cause a denial of service. (CVE-2016-6303)
Shi Lei discovered that OpenSSL incorrectly performed certain message length checks. A remote attacker could possibly use this issue to cause a denial of service. (CVE-2016-6306)
The problem can be corrected by updating your system to the following package versions:
To update your system, please follow these instructions: https://wiki.ubuntu.com/Security/Upgrades.
After a standard system update you need to reboot your computer to make all the necessary changes.