cavsdec.c in libavcodec in FFmpeg before 0.7.4 and 0.8.x before 0.8.3 allows remote attackers to cause a denial of service (incorrect write operation and application crash) via an invalid bitstream in a Chinese AVS video (aka CAVS) file, related to the decode_residual_block, check_for_slice, and cavs_decode_frame functions, a different vulnerability than CVE-2011-3362.