USN-1457-1: Linux kernel vulnerabilities

Ubuntu Security Notice USN-1457-1

31st May, 2012

linux vulnerabilities

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 version:

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

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.

References

CVE-2011-4131, CVE-2012-1601, CVE-2012-2121, CVE-2012-2123, CVE-2012-2133