The decode_slice_header function in libavcodec/h264.c in FFmpeg before 1.1.2 does not properly check when the pixel format changes, which allows remote attackers to have unspecified impact via crafted H.264 video data, related to an out-of-bounds array access.
The product receives input or data, but it does not validate or incorrectly validates that the input has the properties that are required to process the data safely and correctly.