MPlayer is a media player including support for a wide range of audio and video formats.
k`sOSe reported an integer overflow vulnerability in the sdpplin_parse() function in the file stream/realrtsp/sdpplin.c, which can be exploited to overwrite arbitrary memory regions via an overly large "StreamCount" SDP parameter.
A remote attacker could entice a user to open a specially crafted media file, possibly resulting in the execution of arbitrary code with the privileges of the user running MPlayer.
There is no known workaround at this time.
All MPlayer users should upgrade to the latest version:
# emerge --sync
# emerge --ask --oneshot --verbose ">=media-video/mplayer-1.0_rc2_p26753"