---
id: "CVE-2026-125201"
page: "https://infrastack.ai/live/CVE-2026-125201"
kind: "vulnerability"
aliases: ["CVE-2026-125201"]
title: "FFmpeg: crafted AV1 stream overflows heap during Vulkan decoding"
severity: "high"
cvss: 7.3
epss: null
exploited: false
status: "open"
category: "package"
products: []
ecosystems: []
tags: ["ffmpeg", "libavcodec", "package", "video-processing", "vulkan"]
not_affected_if: ["no-vulkan-av1-decoding", "other-ffmpeg-versions", "trusted-input-only"]
published_at: "2026-11-09T19:16:56+00:00"
first_seen_at: "2026-11-09T19:28:18+00:00"
updated_at: "2026-11-09T19:30:11+00:00"
sources: [{"source": "nvd", "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-125201", "first_seen_at": "2026-11-09T19:28:18+00:00"}]
exploit_sources: []
---

# FFmpeg: crafted AV1 stream overflows heap during Vulkan decoding

Link for people: https://infrastack.ai/live/CVE-2026-125201 (this .md is for agents)

FFmpeg's Vulkan AV1 decoder checks the tile-count limit only on entry, so a crafted AV1 stream with more than 256 tiles writes past a heap buffer. An attacker who gets a victim to decode such a file can corrupt heap memory, which may lead to code execution.

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

## How to check

- Run `ffmpeg -version` and compare against the fixed ranges: 7.0 before `8.1.3` and 9.x before `9.0.2`.
- Check whether ffmpeg is built with Vulkan AV1 hardware decoding enabled (the vulkan_av1 decoder), since the flaw needs it.

## Fix

- FFmpeg 7.0 through 8.1.x: move to `8.1.3`.
- FFmpeg 9.x: move to `9.0.2`.

## Timeline

- 2026-11-09T19:28:18+00:00 nvd https://nvd.nist.gov/vuln/detail/CVE-2026-125201

## Documents

- [advisory] Third-party advisory: www.vulncheck.com https://www.vulncheck.com/advisories/ffmpeg-7.0-before-8.1.3-and-9-x-before-9.0.2-heap-overflow-via-vulkan-av1-c
- [fix] Patch: github.com https://github.com/FFmpeg/FFmpeg/commit/d29ff884221042af219e53cc339a62356b061816

## From the sources

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.

---

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