Integer underflow in the asfrtp_parse_packet function in libavformat/rtpdec_asf.c in FFmpeg before 0.8.3 allows remote attackers to execute arbitrary code via a crafted ASF packet.

References

• https://nvd.nist.gov/vuln/detail/CVE-2011-4031
• http://git.videolan.org/?p=ffmpeg.git;a=commit;h=c2a2ad133eb9d42361804a568dee336992349a5e
• http://git.videolan.org/?p=ffmpeg.git;a=shortlog;h=n0.8.3
• http://technet.microsoft.com/en-us/security/msvr/msvr11-012