Ubuntu: 1457-1: Linux kernel vulnerabilities
Posted by Benjamin D. Thomas   
Ubuntu Several security issues were fixed in the kernel.
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Ubuntu Security Notice USN-1457-1
May 31, 2012

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

- Ubuntu 11.04

Summary:

Several security issues were fixed in the kernel.

Software Description:
- linux: Linux kernel

Details:

Andy Adamson discovered a flaw in the Linux kernel's NFSv4 implementation.
A remote NFS server (attacker) could exploit this flaw to cause a denial of
service. (CVE-2011-4131)

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)

A flaw was discovered in the Linux kernel's KVM (kernel virtual machine).
An administrative user in the guest OS could leverage this flaw to cause a
denial of service in the host OS. (CVE-2012-2121)

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)

Schacher Raindel discovered a flaw in the Linux kernel's memory handling
when hugetlb is enabled. An unprivileged local attacker could exploit this
flaw to cause a denial of service and potentially gain higher privileges.
(CVE-2012-2133)

Update instructions:

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

Ubuntu 11.04:
  linux-image-2.6.38-15-generic   2.6.38-15.60
  linux-image-2.6.38-15-generic-pae  2.6.38-15.60
  linux-image-2.6.38-15-omap      2.6.38-15.60
  linux-image-2.6.38-15-powerpc   2.6.38-15.60
  linux-image-2.6.38-15-powerpc-smp  2.6.38-15.60
  linux-image-2.6.38-15-powerpc64-smp  2.6.38-15.60
  linux-image-2.6.38-15-server    2.6.38-15.60
  linux-image-2.6.38-15-versatile  2.6.38-15.60
  linux-image-2.6.38-15-virtual   2.6.38-15.60

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

References:
  http://www.ubuntu.com/usn/usn-1457-1
  CVE-2011-4131, CVE-2012-1601, CVE-2012-2121, CVE-2012-2123,
  CVE-2012-2133

Package Information:
  https://launchpad.net/ubuntu/+source/linux/2.6.38-15.60