An exploitable integer overflow vulnerability exists within the MPEG-4
decoding functionality of the GPAC Project on Advanced Content library
v1.0.1. The library will actually reuse the parser for atoms with the
“stsz” FOURCC code when parsing atoms that use the “stz2” FOURCC code and
can cause an integer overflow due to unchecked arithmetic resulting in a
heap-based buffer overflow that causes memory corruption. An attacker can
convince a user to open a video to trigger this vulnerability.