---
id: "CVE-2026-125252"
page: "https://infrastack.ai/live/CVE-2026-125252"
kind: "vulnerability"
aliases: ["CVE-2026-125252"]
title: "FFmpeg: crafted video with slice parse errors leaks memory until exhausted"
severity: "medium"
cvss: 5.7
epss: null
exploited: false
status: "open"
category: "runtime"
products: []
ecosystems: []
tags: ["ffmpeg", "media-processing", "runtime", "self-hosted", "vaapi"]
not_affected_if: ["no-vaapi-decoding", "trusted-input-only"]
published_at: "2026-11-09T20:18:11+00:00"
first_seen_at: "2026-11-09T20:48:13+00:00"
updated_at: "2026-11-09T20:49:57+00:00"
sources: [{"source": "nvd", "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-125252", "first_seen_at": "2026-11-09T20:48:13+00:00"}]
exploit_sources: []
---

# FFmpeg: crafted video with slice parse errors leaks memory until exhausted

Link for people: https://infrastack.ai/live/CVE-2026-125252 (this .md is for agents)

FFmpeg through 9.0.2 leaks VA parameter and slice buffers in its VAAPI hardware decoder when later slices of a stream fail to parse. An attacker who supplies crafted H.264 or other VAAPI-decoded video can exhaust the memory of the process decoding it.

_Summary, check and fix written by a model from the sources; labelled as such._

## How to check

- Check the installed FFmpeg version with `ffmpeg -version` and compare it with the fixed releases.
- Check whether FFmpeg decodes untrusted video through VAAPI hardware acceleration (`-hwaccel vaapi`) or through a library that calls libavcodec.

## Fix

- FFmpeg: move past `9.0.2`; the patch commits are linked from the sources, but the sources do not name the exact fixed release.

## Timeline

- 2026-11-09T20:48:13+00:00 nvd https://nvd.nist.gov/vuln/detail/CVE-2026-125252

## Documents

- [advisory] Third-party advisory: www.vulncheck.com https://www.vulncheck.com/advisories/ffmpeg-through-9.0.2-vaapi-memory-leak-via-abandoned-picture-buffers
- [fix] Patch: github.com https://github.com/FFmpeg/FFmpeg/commit/4221a63ce869ade862557ca64693bf77f5032971
- [fix] Patch: github.com https://github.com/FFmpeg/FFmpeg/commit/838c660bb3cd66ba74981b453c14c79214f6ef92

## From the sources

FFmpeg through 9.0.2 contains a memory leak vulnerability in libavcodec/vaapi_decode.c that allows attackers to exhaust memory by supplying streams with slice parse errors. Attackers can craft H.264 or other VAAPI-decoded video where later slices fail to parse on every frame, continuously leaking VA parameter and slice buffers plus driver and heap memory.

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