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Ubuntu 11.04 USN-1285-1 Critical: Kernel Access Flaws and DOS Threats

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Calendar Grey November 29, 2011
Scroller Ubuntu
Major kernel vulnerabilities addressed in Ubuntu 11.04 highlighting denial of service risks and accessibility concerns. Users should apply updates urgently.
Several security issues were fixed in the kernel.

Summary

Several security issues were fixed in the kernel.

Software Description:

- linux: Linux kernel

Details:

Andrea Righi discovered a race condition in the KSM memory merging support.

If KSM was being used, a local attacker could exploit this to crash the

system, leading to a denial of service. (CVE-2011-2183)

Vasily Averin discovered that the NFS Lock Manager (NLM) incorrectly

handled unlock requests. A local attacker could exploit this to cause a

denial of service. (CVE-2011-2491)

Vasiliy Kulikov discovered that taskstats did not enforce access

restrictions. A local attacker could exploit this to read certain

information, leading to a loss of privacy. (CVE-2011-2494)

Vasiliy Kulikov discovered that /proc/PID/io did not enforce access

restrictions. A local attacker could exploit this to read certain

information, leading to a loss of privacy. (CVE-2011-2495)

It was discovered that the wireless stack incorrectly verified SSID

lengths. A local attacker coul...

Read the Full Advisory

Topics%20covered

Topics Covered

security advisory denial of service kernel ubuntu accessibility flaw

Update Instructions

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

Ubuntu 11.04:
  linux-image-2.6.38-13-generic   2.6.38-13.52
  linux-image-2.6.38-13-generic-pae  2.6.38-13.52
  linux-image-2.6.38-13-omap      2.6.38-13.52
  linux-image-2.6.38-13-powerpc   2.6.38-13.52
  linux-image-2.6.38-13-powerpc-smp  2.6.38-13.52
  linux-image-2.6.38-13-powerpc64-smp  2.6.38-13.52
  linux-image-2.6.38-13-server    2.6.38-13.52
  linux-image-2.6.38-13-versatile  2.6.38-13.52
  linux-image-2.6.38-13-virtual   2.6.38-13.52

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-1285-1

CVE-2011-2183, CVE-2011-2491, CVE-2011-2494, CVE-2011-2495,

CVE-2011-2517, CVE-2011-2905, CVE-2011-2909

Severity
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Critical

November 29, 2011

Topics%20covered

Topics Covered

security advisory denial of service kernel ubuntu accessibility flaw

Package Information

https://launchpad.net/ubuntu/+source/linux/2.6.38-13.52

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