---
id: CVE-2026-125251
title: FFmpeg through 9.0.2 VVC Decoder Heap Out-of-Bounds Write via refs.c
summary: >-
  FFmpeg through 9.0.2 contains an integer overflow vulnerability in the VVC
  decoder alloc_frame() function in libavcodec/vvc/refs.c that undersizes the
  reference picture list allocation on 32-bit builds. Attackers can supply a
  crafted VVC…
severity: high
cvss: 7
cvssVector: 'CVSS:3.1/AV:L/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:H'
cvssSource: cna
cwe:
  - CWE-190
vendor: FFmpeg
product: FFmpeg
affected:
  - FFmpeg <= 9.0.2
published: '2026-11-09'
updated: '2026-11-09'
sourceUpdated: '2026-11-09T19:11:56.865Z'
source: CVEORG
sourceUrl: 'https://www.cve.org/CVERecord?id=CVE-2026-125251'
references:
  - url: 'https://code.ffmpeg.org/FFmpeg/FFmpeg/pulls/25572'
  - url: >-
      https://github.com/FFmpeg/FFmpeg/commit/053660fdb0d2403b838690689c47ad7685c3b10b
    label: Patch Commit
  - url: 'https://github.com/FFmpeg/FFmpeg/blob/n9.0.2/libavcodec/vvc/refs.c#L148'
  - url: 'https://github.com/FFmpeg/FFmpeg'
  - url: >-
      https://www.vulncheck.com/advisories/ffmpeg-through-9.0.2-vvc-decoder-heap-out-of-bounds-write-via-refs-c
    label: >-
      VulnCheck Advisory: FFmpeg through 9.0.2 VVC Decoder Heap Out-of-Bounds
      Write via refs.c
tags:
  - cve.org
ingestedAt: '2026-11-09T19:18:02.572Z'
---

## Overview

FFmpeg through 9.0.2 contains an integer overflow vulnerability in the VVC decoder alloc_frame() function in libavcodec/vvc/refs.c that undersizes the reference picture list allocation on 32-bit builds. Attackers can supply a crafted VVC (H.266) file with a very large number of NAL units per access unit to trigger heap out-of-bounds writes and corrupt memory.

## Affected

- `FFmpeg <= 9.0.2`

## Remediation

Refer to the linked advisories for vendor-supplied fixes and affected version ranges.