The cdxldecodeframe function in libavcodec/cdxl.c in FFmpeg 2.8.x before 2.8.12, 3.0.x before 3.0.8, 3.1.x before 3.1.8, 3.2.x before 3.2.5, and 3.3.x before 3.3.1 does not exclude the CHUNKY format, which allows remote attackers to cause a denial of service (heap-based buffer overflow and application crash) or possibly have unspecified other impact via a crafted file.