10 - USN-2914-1

A security issue affects these releases of Ubuntu and its derivatives:

- Ubuntu 15.10 - Ubuntu 14.04 LTS - Ubuntu 12.04 LTS

Summary:

Several security issues were fixed in OpenSSL.

Software Description: - openssl: Secure Socket Layer (SSL) cryptographic library and tools

Details:

Yuval Yarom, Daniel Genkin, and Nadia Heninger discovered that OpenSSL was vulnerable to a side-channel attack on modular exponentiation. On certain CPUs, a local attacker could possibly use this issue to recover RSA keys. This flaw is known as CacheBleed. (CVE-2016-0702)

Adam Langley discovered that OpenSSL incorrectly handled memory when parsing DSA private keys. A remote attacker could use this issue to cause OpenSSL to crash, resulting in a denial of service, or possibly execute arbitrary code. (CVE-2016-0705)

Guido Vranken discovered that OpenSSL incorrectly handled hex digit calculation in the BN_hex2bn function. A remote attacker could use this issue to cause OpenSSL to crash, resulting in a denial of service, or possibly execute arbitrary code. (CVE-2016-0797)

Emilia Käsper discovered that OpenSSL incorrectly handled memory when performing SRP user database lookups. A remote attacker could possibly use this issue to cause OpenSSL to consume memory, resulting in a denial of service. (CVE-2016-0798)

Guido Vranken discovered that OpenSSL incorrectly handled memory when printing very long strings. A remote attacker could use this issue to cause OpenSSL to crash, resulting in a denial of service, or possibly execute arbitrary code. (CVE-2016-0799)

Update instructions:

The problem can be corrected by updating your system to the following package versions:

Ubuntu 15.10:
libssl1.0.0 1.0.2d-0ubuntu1.4

Ubuntu 14.04 LTS:
libssl1.0.0 1.0.1f-1ubuntu2.18

Ubuntu 12.04 LTS:
libssl1.0.0 1.0.1-4ubuntu5.35

After a standard system update you need to reboot your computer to make all the necessary changes.

References:
http://www.ubuntu.com/usn/usn-2914-1
CVE-2016-0702, CVE-2016-0705, CVE-2016-0797, CVE-2016-0798,
CVE-2016-0799

Package Information:
https://launchpad.net/ubuntu/+source/openssl/1.0.2d-0ubuntu1.4
https://launchpad.net/ubuntu/+source/openssl/1.0.1f-1ubuntu2.18
https://launchpad.net/ubuntu/+source/openssl/1.0.1-4ubuntu5.35