The GStreamer FFmpeg plugin uses code from the FFmpeg library to provide fast colorspace conversion and multimedia decoders to the GStreamer open source media framework.
The GStreamer FFmpeg plugin contains derived code from the FFmpeg library, which is vulnerable to a heap overflow in the "avcodec_default_get_buffer()" function discovered by Simon Kilvington (see GLSA 200601-06).
A remote attacker could entice a user to run an application using the GStreamer FFmpeg plugin on a maliciously crafted PIX_FMT_PAL8 format image file (like PNG images), possibly leading to the execution of arbitrary code with the permissions of the user running the application.
There is no known workaround at this time.
All GStreamer FFmpeg plugin users should upgrade to the latest version:
# emerge --sync
# emerge --ask --oneshot --verbose ">=media-plugins/gst-plugins-ffmpeg-0.8.7-r1"