An exploitable integer truncation vulnerability exists within the MPEG-4 decoding functionality of the GPAC Project on Advanced Content lib…

published 2021-08-16 5 y ago modified 2026-06-17 4 mo ago also EUVD-2021-9032

cvss: 8.8; version 3.0, CNA
cisa kev: Not listed; not in CISA's catalog
epss: 1.6%; EPSS 1.6% chance of exploitation in 30 days, percentile 76%
public exploits: 0; none known

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.

Patch / fix

distros 1

gpac Debian 11 1.0.1+dfsg1-4+deb11u1

debian advisories DEBIAN-CVE-2021-21861

Exploit prediction

1.63% chance of exploitation in the next 30 days, higher than 76% of all scored CVEs (FIRST EPSS, 2026-11-08).

Exploits and checks

talosintelligence.com https://talosintelligence.com/vulnerability_reports/TALOS-2021-1298 referenced PoC, tagged "exploit" by a source, unverified

CVSS scores

assigned by	version	score	vector
CNA	3.0	8.8	CVSS:3.0/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
NVD	3.1	8.8	CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
NVD	2.0	6.8	AV:N/AC:M/Au:N/C:P/I:P/A:P

Affected products

n/a GPAC Project

Classification

Weakness

CWE-680 Integer Overflow to Buffer Overflow
CWE-681 Incorrect Conversion between Numeric Types

References

talosintelligence.com /vulnerability_reports/TALOS-2021-1298
exploit, third-party-advisory
debian.org /security/2021/dsa-4966
vendor-advisory, third-party-advisory

Sources

CVE List CVE-2021-21861
NVD CVE-2021-21861

Fencer Vulns keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.

Summary