USN-1431-1: Linux kernel vulnerabilities

1 May 2012

linux vulnerabilities

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

  • Ubuntu 11.10

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)

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)

A flaw was discovered in the Linux kernel’s cgroups subset. A local attacker could use this flaw to crash the system. (CVE-2012-1146)

A flaw was found in the Linux kernel’s handling of paged memory. A local unprivileged user, or a privileged user within a KVM guest, could exploit this flaw to crash the system. (CVE-2012-1179)

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 11.10
linux-image-3.0.0-19-generic - 3.0.0-19.33
linux-image-3.0.0-19-generic-pae - 3.0.0-19.33
linux-image-3.0.0-19-omap - 3.0.0-19.33
linux-image-3.0.0-19-powerpc - 3.0.0-19.33
linux-image-3.0.0-19-powerpc-smp - 3.0.0-19.33
linux-image-3.0.0-19-powerpc64-smp - 3.0.0-19.33
linux-image-3.0.0-19-server - 3.0.0-19.33
linux-image-3.0.0-19-virtual - 3.0.0-19.33

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