CVE-2021-21861

Severity: high (CVSS 8.8 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 1.6% probability of exploitation in the next 30 days
Public exploit or detection template: yes
Published: 2021-08-16 · updated 2026-06-17
Weakness: CWE-680

Description

An exploitable integer truncation vulnerability exists within the MPEG-4 decoding functionality of the GPAC Project on Advanced Content library v1.0.1. When processing the 'hdlr' FOURCC code, a specially crafted MPEG-4 input can cause an improper memory allocation 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.

Affected products

Debian Linux: 11.0
GPAC: 1.0.1

References

https://talosintelligence.com/vulnerability_reports/TALOS-2021-1298
https://www.debian.org/security/2021/dsa-4966
https://talosintelligence.com/vulnerability_reports/TALOS-2021-1298
https://www.debian.org/security/2021/dsa-4966

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