1. Ubuntu Security Notices
  2. USN-1448-1

USN-1448-1: Linux kernel vulnerabilities

Publication date

21 May 2012

Overview

Several security issues were fixed in the kernel.

Releases

Packages

Details

A flaw was found in the Linux kernel's KVM (Kernel Virtual Machine) virtual
cpu setup. An unprivileged local user could exploit this flaw to crash the
system leading to a denial of service. (CVE-2012-1601)

Steve Grubb reported a flaw with Linux fscaps (file system base
capabilities) when used to increase the permissions of a process. For
application on which fscaps are in use a local attacker can disable address
space randomization to make attacking the process with raised privileges
easier. (CVE-2012-2123)

A flaw was found in how the Linux kernel passed the replacement session
keyring to a child process. An unprivileged local user could exploit this
flaw to cause a denial of service (panic). (CVE-2012-2745)

A flaw was found in the Linux kernel's KVM (Kernel Virtual Machine) virtual
cpu setup. An unprivileged local user could exploit this flaw to crash the
system leading to a denial of service. (CVE-2012-1601)

Steve Grubb reported a flaw with Linux fscaps (file system base
capabilities) when used to increase the permissions of a process. For
application on which fscaps are in use a local attacker can disable address
space randomization to make attacking the process with raised privileges
easier. (CVE-2012-2123)

A flaw was found in how the Linux kernel passed the replacement session
keyring to a child process. An unprivileged local user could exploit this
flaw to cause a denial of service (panic). (CVE-2012-2745)

Update instructions

After a standard system update you need to reboot your computer to make all the necessary changes.

Learn more about how to get the fixes.

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.

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

Ubuntu Release Package Version
12.04 precise linux-image-3.2.0-24-generic-pae –  3.2.0-24.38
linux-image-3.2.0-24-powerpc64-smp –  3.2.0-24.38
linux-image-3.2.0-24-generic –  3.2.0-24.38
linux-image-3.2.0-24-virtual –  3.2.0-24.38
linux-image-3.2.0-24-omap –  3.2.0-24.38
linux-image-3.2.0-24-powerpc-smp –  3.2.0-24.38

Reduce your security exposure

Ubuntu Pro provides ten-year security coverage to 25,000+ packages in Main and Universe repositories, and it is free for up to five machines.

Get Ubuntu Pro

References

Have additional questions?

Talk to a member of the team ›