sudo 1.6.x before 1.6.9p21, when the runas_default option is used, does not properly set group memberships, which allows local users to gain privileges via a sudo command.

sudo 1.6.x before 1.6.9p21 and 1.7.x before 1.7.2p4, when a pseudo-command is enabled, permits a match between the name of the pseudo-command and the name of an executable file in an arbitrary directory, which allows local users to gain privileges via a crafted executable file, as demonstrated by a file named sudoedit in a user's home directory.

parse.c in sudo 1.6.9p17 through 1.6.9p19 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.