Several security issues were fixed in the kernel.
Dan Rosenberg discovered that the Linux kernel X.25 implementation incorrectly parsed facilities. A remote attacker could exploit this to crash the kernel, leading to a denial of service. (CVE-2010-3873)
25 October 2011
A security issue affects these releases of Ubuntu and its derivatives:
Several security issues were fixed in the kernel.
Dan Rosenberg discovered that the Linux kernel X.25 implementation incorrectly parsed facilities. A remote attacker could exploit this to crash the kernel, leading to a denial of service. (CVE-2010-3873)
Andrea Righi discovered a race condition in the KSM memory merging support. If KSM was being used, a local attacker could exploit this to crash the system, leading to a denial of service. (CVE-2011-2183)
Vasily Averin discovered that the NFS Lock Manager (NLM) incorrectly handled unlock requests. A local attacker could exploit this to cause a denial of service. (CVE-2011-2491)
Vasiliy Kulikov discovered that taskstats did not enforce access restrictions. A local attacker could exploit this to read certain information, leading to a loss of privacy. (CVE-2011-2494)
Vasiliy Kulikov discovered that /proc/PID/io did not enforce access restrictions. A local attacker could exploit this to read certain information, leading to a loss of privacy. (CVE-2011-2495)
It was discovered that the wireless stack incorrectly verified SSID lengths. A local attacker could exploit this to cause a denial of service or gain root privileges. (CVE-2011-2517)
It was discovered that the EXT4 filesystem contained multiple off-by-one flaws. A local attacker could exploit this to crash the system, leading to a denial of service. (CVE-2011-2695)
Christian Ohm discovered that the perf command looks for configuration files in the current directory. If a privileged user were tricked into running perf in a directory containing a malicious configuration file, an attacker could run arbitrary commands and possibly gain privileges. (CVE-2011-2905)
Vasiliy Kulikov discovered that the Comedi driver did not correctly clear memory. A local attacker could exploit this to read kernel stack memory, leading to a loss of privacy. (CVE-2011-2909)
Yogesh Sharma discovered that CIFS did not correctly handle UNCs that had no prefixpaths. A local attacker with access to a CIFS partition could exploit this to crash the system, leading to a denial of service. (CVE-2011-3363)
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.