SynopsisThe remote Ubuntu host is missing one or more security-related patches.
DescriptionGlen Eustace discovered that the DHCP server incorrectly handled IPv6 expiration times. A remote attacker could use this issue to cause DHCP to crash, resulting in a denial of service. This issue only affected Ubuntu 11.04, Ubuntu 11.10 and Ubuntu 12.04 LTS. (CVE-2012-3955)
Dan Rosenberg discovered that the DHCP AppArmor profile could be escaped by using environment variables. This update mitigates the issue by sanitizing certain variables in the DHCP shell scripts.
Note that Tenable Network Security has extracted the preceding description block directly from the Ubuntu security advisory. Tenable has attempted to automatically clean and format it as much as possible without introducing additional issues.
SolutionUpdate the affected packages.