Vulnerability in Ffmpeg
CVE-2026-120247
FFmpeg 2.3 through 9.0.2 contains a use of uninitialized resource vulnerability in the Huffyuv decoder that allows attackers to leak heap memory into decoded pixels via short packed-BGR bitstreams. Attackers can craft a Huffyuv BGR24/BGRA video whose entropy data ends early, causing decode_slice() to add uninitialized s->temp[0] bytes into output frames, exposing heap contents.
Published .
CVSS v3 metric
CVSS v3 base score 5.5 (Medium). Vector: CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:N/A:N.
EPSS exploit prediction
No EPSS score from FIRST.org yet. New CVEs usually get one within a few days; no score means no signal yet, not low risk. How EPSS works.
Affected products
Weakness classification (CWE)
References
- code.ffmpeg.org/FFmpeg/FFmpeg/pulls/24869 (issue-tracking)
- github.com/FFmpeg/FFmpeg/commit/7c73707355708c846f718cca90096bc1a33c8989 (patch)
- github.com/FFmpeg/FFmpeg/blob/n9.0.2/libavcodec/huffyuvdec.c (technical-description)
- github.com/FFmpeg/FFmpeg (product)
- www.vulncheck.com/advisories/ffmpeg-2.3-through-9.0.2-huffyuv-decoder-uninitial… (third-party-advisory)
Frequently asked questions
- What is CVE-2026-120247?
- CVE-2026-120247 is a medium-severity vulnerability in Ffmpeg, classified under Use of Uninitialized Resource. CVSS score: 5.5/10. Published 2026-11-01.
- How severe is CVE-2026-120247?
- Medium severity. CVSS v3 base score is 5.5 out of 10.