Buffer overflow in Ffmpeg
CVE-2026-125262
FFmpeg through 9.0.2 contains a heap buffer overflow vulnerability in libavcodec/lcevcdec.c because LCEVC output picture dimensions are not validated against the allocated frame. Attackers can embed crafted LCEVC enhancement data with differing global configurations in H.264 or HEVC streams to corrupt heap memory in decoding applications.
Vulnerability class: Buffer Overflow
Published .
CVSS v3 metric
CVSS v3 base score 7.8 (High). Vector: CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H.
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/25067 (issue-tracking)
- github.com/FFmpeg/FFmpeg/commit/fd6dfa613a48665dcb8d14186b33dad90aa40ae0 (patch)
- github.com/FFmpeg/FFmpeg/blob/n9.0.2/libavcodec/lcevcdec.c (technical-description)
- github.com/FFmpeg/FFmpeg (product)
- www.vulncheck.com/advisories/ffmpeg-through-9.0.2-heap-buffer-overflow-via-lcev… (third-party-advisory)
Frequently asked questions
- What is CVE-2026-125262?
- CVE-2026-125262 is a high-severity vulnerability in Ffmpeg, classified under Out-of-bounds Write. CVSS score: 7.8/10. Published 2026-11-09.
- How severe is CVE-2026-125262?
- High severity. CVSS v3 base score is 7.8 out of 10.