---
id: CVE-2026-125265
title: FFmpeg through 9.0.2 Use-After-Free via NVDEC Stale Bitstream Pointer
summary: >-
  FFmpeg through 9.0.2 contains a use-after-free vulnerability in
  libavcodec/nvdec.c because ff_nvdec_start_frame() fails to reset
  ctx->bitstream after slice errors. Attackers can supply crafted video that
  abandons a picture before end_fra…
severity: medium
cvss: 5.3
cvssVector: 'CVSS:3.1/AV:L/AC:H/PR:N/UI:R/S:U/C:L/I:N/A:H'
cvssSource: cna
cwe:
  - CWE-416
vendor: FFmpeg
product: FFmpeg
affected:
  - FFmpeg <= 9.0.2
published: '2026-11-09'
updated: '2026-11-09'
sourceUpdated: '2026-11-09T19:12:06.735Z'
source: CVEORG
sourceUrl: 'https://www.cve.org/CVERecord?id=CVE-2026-125265'
references:
  - url: 'https://code.ffmpeg.org/FFmpeg/FFmpeg/pulls/25231'
  - url: >-
      https://github.com/FFmpeg/FFmpeg/commit/03cd7851955c023f1ff4c8a495d47e996d01485a
    label: Patch Commit
  - url: 'https://github.com/FFmpeg/FFmpeg/blob/n9.0.2/libavcodec/nvdec.c#L694'
  - url: 'https://github.com/FFmpeg/FFmpeg'
  - url: >-
      https://www.vulncheck.com/advisories/ffmpeg-through-9.0.2-use-after-free-via-nvdec-stale-bitstream-pointer
    label: >-
      VulnCheck Advisory: FFmpeg through 9.0.2 Use-After-Free via NVDEC Stale
      Bitstream Pointer
tags:
  - cve.org
ingestedAt: '2026-11-09T20:27:27.077Z'
---

## Overview

FFmpeg through 9.0.2 contains a use-after-free vulnerability in libavcodec/nvdec.c because ff_nvdec_start_frame() fails to reset ctx->bitstream after slice errors. Attackers can supply crafted video that abandons a picture before end_frame, causing cuvidDecodePicture() to read freed heap memory, crashing applications or exposing stale heap contents.

## Affected

- `FFmpeg <= 9.0.2`

## Remediation

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