USN-1432-1: Linux kernel vulnerabilities

8 May 2012

linux vulnerabilities

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

  • Ubuntu 11.04

Summary

Several security issues were fixed in the kernel.

Software Description

  • linux - Linux kernel

Details

A flaw was found in the Linux’s kernels ext4 file system when mounted with a journal. A local, unprivileged user could exploit this flaw to cause a denial of service. (CVE-2011-4086)

A flaw was discovered in the Linux kernel’s cifs file system. An unprivileged local user could exploit this flaw to crash the system leading to a denial of service. (CVE-2012-1090)

A flaw was found in the Linux kernel’s ext4 file system when mounting a corrupt filesystem. A user-assisted remote attacker could exploit this flaw to cause a denial of service. (CVE-2012-2100)

Tetsuo Handa reported a flaw in the OOM (out of memory) killer of the Linux kernel. A local unprivileged user can exploit this flaw to cause system unstability and denial of services. (CVE-2012-4398)

Update instructions

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

Ubuntu 11.04
linux-image-2.6.38-15-generic - 2.6.38-15.59
linux-image-2.6.38-15-generic-pae - 2.6.38-15.59
linux-image-2.6.38-15-omap - 2.6.38-15.59
linux-image-2.6.38-15-powerpc - 2.6.38-15.59
linux-image-2.6.38-15-powerpc-smp - 2.6.38-15.59
linux-image-2.6.38-15-powerpc64-smp - 2.6.38-15.59
linux-image-2.6.38-15-server - 2.6.38-15.59
linux-image-2.6.38-15-versatile - 2.6.38-15.59
linux-image-2.6.38-15-virtual - 2.6.38-15.59

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.

References