Xi Wang and Florian Weimer discovered that libssh incorrectly handled memory. A remote attacker could use this to cause libssh to crash, resulting in a denial of service, or possibly execute arbitrary code.
Updated packages are available from security.ubuntu.com.
========================================================================== Ubuntu Security Notice USN-1640-1 November 26, 2012 libssh vulnerabilities ========================================================================== A security issue affects these releases of Ubuntu and its derivatives: - Ubuntu 12.10 - Ubuntu 12.04 LTS - Ubuntu 11.10 - Ubuntu 10.04 LTS Summary: linssh could be made to crash or run programs if it received specially crafted network traffic. Software Description: - libssh: A tiny C SSH library Details: Xi Wang and Florian Weimer discovered that libssh incorrectly handled memory. A remote attacker could use this to cause libssh to crash, resulting in a denial of service, or possibly execute arbitrary code. (CVE-2012-4559, CVE-2012-4560, CVE-2012-4561, CVE-2012-4562) Update instructions: The problem can be corrected by updating your system to the following package versions: Ubuntu 12.10: libssh-4 0.5.2-1ubuntu0.12.10.1 Ubuntu 12.04 LTS: libssh-4 0.5.2-1ubuntu0.12.04.1 Ubuntu 11.10: libssh-4 0.5.2-1ubuntu0.11.10.1 Ubuntu 10.04 LTS: libssh-4 0.4.2-1ubuntu1.1 In general, a standard system update will make all the necessary changes. References: http://www.ubuntu.com/usn/usn-1640-1 CVE-2012-4559, CVE-2012-4560, CVE-2012-4561, CVE-2012-4562 Package Information: https://launchpad.net/ubuntu/+source/libssh/0.5.2-1ubuntu0.12.10.1 https://launchpad.net/ubuntu/+source/libssh/0.5.2-1ubuntu0.12.04.1 https://launchpad.net/ubuntu/+source/libssh/0.5.2-1ubuntu0.11.10.1 https://launchpad.net/ubuntu/+source/libssh/0.4.2-1ubuntu1.1