Several security issues were fixed in the kernel.
An error was discovered in the Linux kernel’s network TUN/TAP device implementation. A local user with access to the TUN/TAP interface (which is not available to unprivileged users until granted by a root user) could exploit this flaw to crash the system or potential gain administrative privileges. (CVE-2012-2136)
14 August 2012
A security issue affects these releases of Ubuntu and its derivatives:
Several security issues were fixed in the kernel.
An error was discovered in the Linux kernel’s network TUN/TAP device implementation. A local user with access to the TUN/TAP interface (which is not available to unprivileged users until granted by a root user) could exploit this flaw to crash the system or potential gain administrative privileges. (CVE-2012-2136)
Ulrich Obergfell discovered an error in the Linux kernel’s memory management subsystem on 32 bit PAE systems with more than 4GB of memory installed. A local unprivileged user could exploit this flaw to crash the system. (CVE-2012-2373)
An error was discovered in the Linux kernel’s memory subsystem (hugetlb). An unprivileged local user could exploit this flaw to cause a denial of service (crash the system). (CVE-2012-2390)
A flaw was discovered in the Linux kernel’s epoll system call. An unprivileged local user could use this flaw to crash the system. (CVE-2012-3375)
Some errors where discovered in the Linux kernel’s UDF file system, which is used to mount some CD-ROMs and DVDs. An unprivileged local user could use these flaws to crash the system. (CVE-2012-3400)
A flaw was discovered in the madvise feature of the Linux kernel’s memory subsystem. An unprivileged local use could exploit the flaw to cause a denial of service (crash the system). (CVE-2012-3511)
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.
ATTENTION: Due to an unavoidable ABI change the kernel updates have been given a new version number, which requires you to recompile and reinstall all third party kernel modules you might have installed. If you use linux-restricted-modules, you have to update that package as well to get modules which work with the new kernel version. Unless you manually uninstalled the standard kernel metapackages (e.g. linux-generic, linux-server, linux-powerpc), a standard system upgrade will automatically perform this as well.