VULNERABILITY INTELLIGENCE

CVE-2021-21840

CVSS score8.8 HIGH

EPSS probability1.70%

CISA KEVNot currently listed

Published2021-08-25

Last modified2026-06-17

CVSS vectorCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H

Description

An exploitable integer overflow vulnerability exists within the MPEG-4 decoding functionality of the GPAC Project on Advanced Content library v1.0.1. A specially crafted MPEG-4 input used to process an atom using the “saio” FOURCC code 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.

Weakness classification

talos-cna@cisco.com: CWE-680
nvd@nist.gov: CWE-119

Primary references

talos-cna@cisco.com — Exploit, Third Party Advisory
talos-cna@cisco.com — Third Party Advisory
af854a3a-2127-422b-91ae-364da2661108 — Exploit, Third Party Advisory
af854a3a-2127-422b-91ae-364da2661108 — Third Party Advisory