Buffer overflow in Ffmpeg
CVE-2026-125201
FFmpeg 7.0 before 8.1.3 and 9.x before 9.0.2 contains a heap out-of-bounds write vulnerability in vk_av1_decode_slice() in libavcodec/vulkan_av1.c because the tile-count limit is checked only on entry. Attackers can supply a crafted AV1 stream with more than 256 tiles decoded via the Vulkan hardware accelerator to overflow tile_sizes and corrupt heap memory.
Vulnerability class: Buffer Overflow
Published .
CVSS v3 metric
CVSS v3 base score 7.0 (High). Vector: CVSS:3.1/AV:L/AC:H/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/24289 (issue-tracking)
- github.com/FFmpeg/FFmpeg (product)
- github.com/FFmpeg/FFmpeg/blob/n9.0.1/libavcodec/vulkan_av1.c (technical-description)
- github.com/FFmpeg/FFmpeg/commit/d29ff884221042af219e53cc339a62356b061816 (patch)
- www.vulncheck.com/advisories/ffmpeg-7.0-before-8.1.3-and-9-x-before-9.0.2-heap-… (third-party-advisory)
Frequently asked questions
- What is CVE-2026-125201?
- CVE-2026-125201 is a high-severity vulnerability in Ffmpeg, classified under Out-of-bounds Write. CVSS score: 7.0/10. Published 2026-11-09.
- How severe is CVE-2026-125201?
- High severity. CVSS v3 base score is 7.0 out of 10.