USN-1269-1: Linux kernel (EC2) vulnerabilities

21 November 2011

Several security issues were fixed in the kernel.

Reduce your security exposure

Ubuntu Pro provides ten-year security coverage to 25,000+ packages in Main and Universe repositories, and it is free for up to five machines.

Learn more about Ubuntu Pro

Releases

Packages

Details

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)

Robert Swiecki discovered that mapping extensions were incorrectly handled.
A local attacker could exploit this to crash the system, leading to a
denial of service. (CVE-2011-2496)

It was discovered that the wireless stack incorrectly verified SSID
lengths. A local attacker could exploit this to cause a denial of service
or gain root privileges. (CVE-2011-2517)

Ben Pfaff discovered that Classless Queuing Disciplines (qdiscs) were being
incorrectly handled. A local attacker could exploit this to crash the
system, leading to a denial of service. (CVE-2011-2525)

Reduce your security exposure

Ubuntu Pro provides ten-year security coverage to 25,000+ packages in Main and Universe repositories, and it is free for up to five machines.

Learn more about Ubuntu Pro

Update instructions

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

Ubuntu 10.04

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.