---
id: "CVE-2026-125217"
page: "https://infrastack.ai/live/CVE-2026-125217"
kind: "vulnerability"
aliases: ["CVE-2026-125217"]
title: "FFmpeg: uninitialized heap data leaks into RoQ audio output packets"
severity: "medium"
cvss: 4.8
epss: null
exploited: false
status: "open"
category: "package"
products: [{"name": "FFmpeg", "fixed": [], "affected": "", "ecosystem": "vendor"}]
ecosystems: ["vendor"]
tags: ["ffmpeg", "media-processing", "package", "transcoding"]
not_affected_if: ["no-roq-encoding", "trusted-input-only"]
published_at: "2026-11-09T19:16:58+00:00"
first_seen_at: "2026-11-09T19:28:19+00:00"
updated_at: "2026-11-09T19:32:16+00:00"
sources: [{"source": "nvd", "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-125217", "first_seen_at": "2026-11-09T19:28:19+00:00"}]
exploit_sources: []
---

# FFmpeg: uninitialized heap data leaks into RoQ audio output packets

Link for people: https://infrastack.ai/live/CVE-2026-125217 (this .md is for agents)

FFmpeg's RoQ DPCM audio encoder reads uninitialized heap memory when a short stream is flushed early, so stale heap contents get written into output packets. An attacker who supplies a short audio stream under eight frames can leak that heap data into transcoded output.

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

## Affected

- vendor:FFmpeg affected range not listed fixed no fixed version listed

## How to check

- Check the installed FFmpeg version with `ffmpeg -version`; the sources say the flaw covers releases through `9.0.2`.
- Look for RoQ audio encoding (`-c:a roq_dpcm`) in pipelines that transcode untrusted audio.

## Timeline

- 2026-11-09T19:28:19+00:00 nvd https://nvd.nist.gov/vuln/detail/CVE-2026-125217

## Documents

- [advisory] Third-party advisory: www.vulncheck.com https://www.vulncheck.com/advisories/ffmpeg-through-9.0.2-roq-dpcm-encoder-uninitialized-heap-memory-disclosure
- [fix] Patch: github.com https://github.com/FFmpeg/FFmpeg/commit/f71410e0288f0c40ae2fb5e5a4d7428763d08a71

## From the sources

FFmpeg through 9.0.2 contains an uninitialized memory use vulnerability in roq_dpcm_encode_frame() in libavcodec/roqaudioenc.c that encodes stale heap contents when flushed early. Attackers can supply short audio streams under eight frames for RoQ DPCM transcoding, causing DPCM-quantized uninitialized heap data from frame_buffer to leak into output packets.

---

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