The sudo (superuser do) utility allows system administrators to give certain users the ability to run commands as root with logging.
A flaw was discovered in a way sudo handled group specifications in "run as" lists in the sudoers configuration file. If sudo configuration allowed a user to run commands as any user of some group and the user was also a member of that group, sudo incorrectly allowed them to run defined commands with the privileges of any system user. This gave the user unintended privileges. (CVE-2009-0034)
Users of sudo should update to this updated package, which contains a backported patch to resolve this issue.