Vulnerability in Ffmpeg
CVE-2026-125189
FFmpeg 8.1 through 9.0.2 contains a denial of service vulnerability in the lcevc_metadata bitstream filter caused by a process block position mismatch in lcevc_metadata_handle_vui(). Attackers can supply crafted LCEVC access units with two IDR or non-IDR NAL units to trigger an av_assert0 failure in ff_cbs_lcevc_list_add(), aborting the application.
Published .
CVSS v3 metric
CVSS v3 base score 4.7 (Medium). Vector: CVSS:3.1/AV:L/AC:H/PR:N/UI:R/S:U/C:N/I:N/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/25408 (issue-tracking)
- github.com/FFmpeg/FFmpeg (product)
- github.com/FFmpeg/FFmpeg/blob/n9.0.2/libavcodec/bsf/lcevc_metadata.c (technical-description)
- Patch Commit (patch)
- VulnCheck Advisory: FFmpeg 8.1 through 9.0.2 Denial of Service via lcevc_metadata Bitstream Filter (third-party-advisory)
Frequently asked questions
- What is CVE-2026-125189?
- CVE-2026-125189 is a medium-severity vulnerability in Ffmpeg, classified under Reachable Assertion. CVSS score: 4.7/10. Published 2026-11-09.
- How severe is CVE-2026-125189?
- Medium severity. CVSS v3 base score is 4.7 out of 10.