6.8 - USN-1242-1

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

- Ubuntu 10.04 LTS

Summary:

Several security issues were fixed in the kernel.

Software Description: - linux-lts-backport-maverick: Linux kernel backport from Maverick

Details:

It was discovered that the security fix for CVE-2010-4250 introduced a regression. A remote attacker could exploit this to crash the system, leading to a denial of service. (CVE-2011-1479)

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 EXT4 filesystem contained multiple off-by-one flaws. A local attacker could exploit this to crash the system, leading to a denial of service. (CVE-2011-2695)

Christian Ohm discovered that the perf command looks for configuration files in the current directory. If a privileged user were tricked into running perf in a directory containing a malicious configuration file, an attacker could run arbitrary commands and possibly gain privileges. (CVE-2011-2905)

Vasiliy Kulikov discovered that the Comedi driver did not correctly clear memory. A local attacker could exploit this to read kernel stack memory, leading to a loss of privacy. (CVE-2011-2909)

Dan Kaminsky discovered that the kernel incorrectly handled random sequence number generation. An attacker could use this flaw to possibly predict sequence numbers and inject packets. (CVE-2011-3188)

Yogesh Sharma discovered that CIFS did not correctly handle UNCs that had no prefixpaths. A local attacker with access to a CIFS partition could exploit this to crash the system, leading to a denial of service. (CVE-2011-3363)

Update instructions:

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

Ubuntu 10.04 LTS:
linux-image-2.6.35-30-generic 2.6.35-30.61~lucid1
linux-image-2.6.35-30-generic-pae 2.6.35-30.61~lucid1
linux-image-2.6.35-30-server 2.6.35-30.61~lucid1
linux-image-2.6.35-30-virtual 2.6.35-30.61~lucid1

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

References:
http://www.ubuntu.com/usn/usn-1242-1
CVE-2011-1479, CVE-2011-2494, CVE-2011-2495, CVE-2011-2695,
CVE-2011-2905, CVE-2011-2909, CVE-2011-3188, CVE-2011-3363

Package Information:
https://launchpad.net/ubuntu/+source/linux-lts-backport-maverick/2.6.35-30.61~lucid1