Vulnerability · Published Aug 19, 2026 · Assigned by VulnCheck

CVE-2026-75141FFmpeg Heap Buffer Overflow in hvcC Box Writer via HEVC Muxing

High 7.8

In plain English

A high-severity heap buffer overflow in FFmpeg from FFmpeg. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.2% (higher than 10% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.

Severity (CVSS 3.1)7.8High

Exploit odds (30 days)0.2%top 90.2% of all CVEs

Exploited in the wildNo reportsCISA SSVC: none

Attack toolingNoneno public tooling known

Official description

FFmpeg before commit acf5d7c contains a heap buffer overflow in the hvcC box writer. When writing an HEVC configuration record with more NAL units of a single type than the count field can represent, the NAL unit count overflows, causing a heap buffer overflow. A crafted HEVC input file triggers the overflow during muxing.

Affected packages & fixed versions

Ecosystem	Package	Fixed in	Advisory
Debian:12	ffmpeg	no fix listed	DEBIAN-CVE-2026-75141
Debian:13	ffmpeg	no fix listed	DEBIAN-CVE-2026-75141
Debian:14	ffmpeg	7:9.0.2-1	DEBIAN-CVE-2026-75141
Ubuntu:26.10	ffmpeg	no fix listed	UBUNTU-CVE-2026-75141

Affected products (as reported)

Vendor	Product	Versions
FFmpeg	FFmpeg	0 – before acf5d7cdc1f9ae8752c23e1ea8d7f355ed780781

Weakness: CWE-122 · Vector: CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H

References

Pull Request issue-tracking
Patch Commit patch
https://www.vulncheck.com/advisories/ffmpeg-heap-buffer-overflow-in-hvcc-box-writer-via-hevc-muxing third-party-advisory