Todd Miller » Sudo : Security Vulnerabilities, CVEs, Published In 2011

check.c in sudo 1.7.x before 1.7.4p5, when a Runas group is configured, does not require a password for command execution that involves a gid change but no uid change, which allows local users to bypass an intended authentication requirement via the -g option to a sudo command.

A certain Fedora patch for parse.c in sudo before 1.7.4p5-1.fc14 on Fedora 14 does not properly interpret a system group (aka %group) in the sudoers file during authorization decisions for a user who belongs to that group, which allows local users to leverage an applicable sudoers file and gain root privileges via a sudo command. NOTE: this vulnerability exists because of a CVE-2009-0034 regression.