Steve Kemp discovered a problem in xsok, a single player strategy game for X11, related to the Sokoban game, which leads a user to execute arbitrary commands under the GID of games.
For the stable distribution (woody) this problem has been fixed in version 1.02-9woody2.
For the unstable distribution (sid) this problem has been fixed in version 1.02-11.
We recommend that you upgrade your xsok package.
MD5 checksums of the listed files are available in the original advisory.