1. Ubuntu Security Notices
  2. USN-1108-2

USN-1108-2: DHCP vulnerability

Publication date

19 April 2011

Overview

An attacker’s DHCP server could send crafted responses to your computer and cause it to run programs as root.

Releases

Packages

Details

USN-1108-1 fixed vulnerabilities in DHCP. Due to an error, the patch to fix
the vulnerability was not properly applied on Ubuntu 9.10 and higher. This
update fixes the problem.

Original advisory details:

Sebastian Krahmer discovered that the dhclient utility incorrectly filtered
crafted responses. An attacker could use this flaw with a malicious DHCP
server to execute arbitrary code, resulting in root privilege escalation.

USN-1108-1 fixed vulnerabilities in DHCP. Due to an error, the patch to fix
the vulnerability was not properly applied on Ubuntu 9.10 and higher. This
update fixes the problem.

Original advisory details:

Sebastian Krahmer discovered that the dhclient utility incorrectly filtered
crafted responses. An attacker could use this flaw with a malicious DHCP
server to execute arbitrary code, resulting in root privilege escalation.

Update instructions

In general, a standard system update will make all the necessary changes.

Learn more about how to get the fixes.

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

Ubuntu Release Package Version
9.10 karmic dhcp3-client –  3.1.2-1ubuntu7.3
10.10 maverick dhcp3-client –  3.1.3-2ubuntu6.2
10.04 lucid dhcp3-client –  3.1.3-2ubuntu3.2

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.

Get Ubuntu Pro

References

Have additional questions?

Talk to a member of the team ›