libavcodec/utvideodec.c in FFmpeg before 2.5.2 does not check for a zero value of a slice height, which allows remote attackers to cause a denial of service…

libavcodec/utvideodec.c in FFmpeg before 2.5.2 does not check for a zero value of a slice height, which allows remote attackers to cause a denial of service (out-of-bounds array access) or possibly have unspecified other impact via crafted Ut Video data, related to the (1) restore_median and (2) restore_median_il functions.