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Ubuntu 11.10: USN-1363-1 Moderate: Kernel Denial Of Service Issues

ubuntu
Calendar Grey February 13, 2012
Scroller Ubuntu
Numerous vulnerabilities addressed in Ubuntu's Linux kernel, necessitating patches and possible adjustments to system settings.
Several security issues were fixed in the kernel.

Summary

Several security issues were fixed in the kernel.

Software Description:

- linux: Linux kernel

Details:

A flaw was found in KVM's Programmable Interval Timer (PIT). When a virtual

interrupt control is not available a local user could use this to cause a

denial of service by starting a timer. (CVE-2011-4622)

A flaw was discovered in the XFS filesystem. If a local user mounts a

specially crafted XFS image it could potential execute arbitrary code on

the system. (CVE-2012-0038)

Andy Whitcroft discovered a that the Overlayfs filesystem was not doing the

extended permission checks needed by cgroups and Linux Security Modules

(LSMs). A local user could exploit this to by-pass security policy and

access files that should not be accessible. (CVE-2012-0055)

A flaw was found in the linux kernels IPv4 IGMP query processing. A remote

attacker could exploit this to cause a denial of service. (CVE-2012-0207)

Topics%20covered

Topics Covered

security advisory denial of service Ubuntu kernel filesystem XFS Overlayfs

Update Instructions

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

Ubuntu 11.10:
  linux-image-3.0.0-16-generic    3.0.0-16.28
  linux-image-3.0.0-16-generic-pae  3.0.0-16.28
  linux-image-3.0.0-16-omap       3.0.0-16.28
  linux-image-3.0.0-16-powerpc    3.0.0-16.28
  linux-image-3.0.0-16-powerpc-smp  3.0.0-16.28
  linux-image-3.0.0-16-powerpc64-smp  3.0.0-16.28
  linux-image-3.0.0-16-server     3.0.0-16.28
  linux-image-3.0.0-16-virtual    3.0.0-16.28

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

https://ubuntu.com/security/notices/USN-1363-1

CVE-2011-4622, CVE-2012-0038, CVE-2012-0055, CVE-2012-0207

February 13, 2012

Topics%20covered

Topics Covered

security advisory denial of service Ubuntu kernel filesystem XFS Overlayfs

Package Information

https://launchpad.net/ubuntu/+source/linux/3.0.0-16.28

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