xine-lib is the core library package for the xine media player.
xine-lib does not check boundaries on data being read into buffers from DMO video files in code that is shared with MPlayer (DMO_VideoDecoder.c).
An attacker could entice a user to play a specially crafted DMO video file with a player using xine-lib, potentially resulting in the execution of arbitrary code with the privileges of the user running the player.
There is no known workaround at this time.
All xine-lib users on the x86 platform should upgrade to the latest version:
# emerge --sync
# emerge --ask --oneshot --verbose ">=media-libs/xine-lib-1.1.4-r2"