The ffmpeg lavf demuxer allows user-assisted attackers to cause a denial of service (application crash) via a crafted GIF file, possibly related to gstreamer, as demonstrated by lol-giftopnm.gif.
https://exchange.xforce.ibmcloud.com/vulnerabilities/44210
http://www.securityfocus.com/bid/31234
http://www.openwall.com/lists/oss-security/2008/07/13/3
http://www.mandriva.com/security/advisories?name=MDVSA-2009:297