The ff_mpv_common_init function in libavcodec/mpegvideo.c in FFmpeg before 2.7.2 does not properly maintain the encoding context, which allows remote attackers to cause a denial of service (invalid pointer access) or possibly have unspecified other impact via crafted MPEG data.

The ff_sbr_apply function in libavcodec/aacsbr.c in FFmpeg before 2.7.2 does not check for a matching AAC frame syntax element before proceeding with Spectral Band Replication calculations, which allows remote attackers to cause a denial of service (out-of-bounds array access) or possibly have unspecified other impact via crafted AAC data.

Multiple integer underflows in the ff_mjpeg_decode_frame function in libavcodec/mjpegdec.c in FFmpeg before 2.7.2 allow remote attackers to cause a denial of service (out-of-bounds array access) or possibly have unspecified other impact via crafted MJPEG data.

The decode_ihdr_chunk function in libavcodec/pngdec.c in FFmpeg before 2.7.2 does not enforce uniqueness of the IHDR (aka image header) chunk in a PNG image, which allows remote attackers to cause a denial of service (out-of-bounds array access) or possibly have unspecified other impact via a crafted image with two or more of these chunks.