USN-2914-1: OpenSSL vulnerabilities

Ubuntu Security Notice USN-2914-1

1st March, 2016

openssl vulnerabilities

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 version:

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

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.

References

CVE-2016-0702, CVE-2016-0705, CVE-2016-0797, CVE-2016-0798, CVE-2016-0799