Ubuntu Security Notice USN-1426-1

24th April, 2012

linux-ec2 vulnerabilities

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

• Ubuntu 10.04 LTS

Summary

Several security issues were fixed in the kernel.

Software description

• linux-ec2 - Linux kernel for EC2

Details

Sasha Levin discovered a flaw in the permission checking for device
assignments requested via the kvm ioctl in the Linux kernel. A local user
could use this flaw to crash the system causing a denial of service.
(CVE-2011-4347)

Stephan Bärwolf discovered a flaw in the KVM (kernel-based virtual
machine) subsystem of the Linux kernel. A local unprivileged user can crash
use this flaw to crash VMs causing a deny of service. (CVE-2012-0045)

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)

H. Peter Anvin reported a flaw in the Linux kernel that could crash the
system. A local user could exploit this flaw to crash the system.
(CVE-2012-1097)

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 version:

Ubuntu 10.04 LTS:

linux-image-2.6.32-345-ec2 2.6.32-345.47

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

CVE-2011-4347, CVE-2012-0045, CVE-2012-1090, CVE-2012-1097, CVE-2012-4398