The libcgroup packages provide tools and libraries to control and monitor control groups. A heap-based buffer overflow flaw was found in the way libcgroup converted a list of user-provided controllers for a particular task into an array of strings. A local attacker could use this flaw to escalate their privileges via a specially-crafted list of controllers. It was discovered that libcgroup did not properly check the origin of Netlink messages. A local attacker could use this flaw to send crafted Netlink messages to the cgrulesengd daemon, causing it to put processes into one or more existing control groups, based on the attacker"s choosing, possibly allowing the particular tasks to run with more resources than originally intended. Red Hat would like to thank Nelson Elhage for reporting the CVE-2011-1006 issue. All libcgroup users should upgrade to these updated packages, which contain backported patches to correct these issues.