---
id: "CVE-2026-125224"
page: "https://infrastack.ai/live/CVE-2026-125224"
kind: "vulnerability"
aliases: ["CVE-2026-125224"]
title: "FFmpeg: crafted Vorbis streams make demuxing re-parse data and exhaust CPU"
severity: "medium"
cvss: 6.8
epss: null
exploited: false
status: "open"
category: "runtime"
products: []
ecosystems: []
tags: ["ffmpeg", "libavcodec", "media-processing", "runtime"]
not_affected_if: ["no-untrusted-media", "trusted-input-only"]
published_at: "2026-11-09T19:16:59+00:00"
first_seen_at: "2026-11-09T19:28:19+00:00"
updated_at: "2026-11-09T19:30:33+00:00"
sources: [{"source": "nvd", "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-125224", "first_seen_at": "2026-11-09T19:28:19+00:00"}]
exploit_sources: []
---

# FFmpeg: crafted Vorbis streams make demuxing re-parse data and exhaust CPU

Link for people: https://infrastack.ai/live/CVE-2026-125224 (this .md is for agents)

FFmpeg through 9.0.2 re-parses invalid Vorbis extradata for every packet in libavcodec's vorbis parser. An attacker who supplies a crafted Ogg or Matroska file with large invalid extradata and many packets can exhaust CPU during demuxing or probing.

_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 release named in the patch link.
- Find services that run FFmpeg or libavcodec on user-uploaded media (thumbnailing, transcoding, probing).

## Timeline

- 2026-11-09T19:28:19+00:00 nvd https://nvd.nist.gov/vuln/detail/CVE-2026-125224

## Documents

- [advisory] Third-party advisory: www.vulncheck.com https://www.vulncheck.com/advisories/ffmpeg-through-9.0.2-vorbis-parser-cpu-exhaustion-via-invalid-extradata
- [fix] Patch: github.com https://github.com/FFmpeg/FFmpeg/commit/90f5e61a1da2dcc0050169af8ca593530f26071b

## From the sources

FFmpeg through 9.0.2 contains a denial of service vulnerability in libavcodec/vorbis_parser.c that re-parses invalid extradata for every packet when valid_extradata remains false. Attackers can supply crafted Ogg or Matroska Vorbis streams with large invalid extradata and many packets to exhaust CPU during demuxing or probing.

---

_Free to read, with fair use of about 60 pages a minute. For higher limits or API access: sales@infrastack.ai_