CVE-2021-21851 — Integer Overflow to Buffer Overflow in Gpac

Multiple exploitable integer overflow vulnerabilities exist within the MPEG-4 decoding functionality of the GPAC Project on Advanced Content library v1.0.1. A specially crafted MPEG-4 input at “csgp” decoder sample group description indices 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.