---
id: CVE-2026-125195
title: >-
  FFmpeg through 9.0.2 Uninitialized Memory Disclosure via ADPCM_MS Trellis
  Encoding
summary: >-
  FFmpeg through 9.0.2 contains an uninitialized memory disclosure vulnerability
  in adpcm_encode_frame() in libavcodec/adpcmenc.c that leaks heap bytes when
  encoding mono ADPCM_MS audio with trellis enabled. Attackers submitting audio
  to a…
severity: low
cvss: 2.5
cvssVector: 'CVSS:3.1/AV:L/AC:H/PR:N/UI:R/S:U/C:L/I:N/A:N'
cvssSource: cna
cwe:
  - CWE-908
vendor: FFmpeg
product: FFmpeg
affected:
  - FFmpeg <= 9.0.2
published: '2026-11-09'
updated: '2026-11-09'
sourceUpdated: '2026-11-09T19:11:16.544Z'
source: CVEORG
sourceUrl: 'https://www.cve.org/CVERecord?id=CVE-2026-125195'
references:
  - url: 'https://code.ffmpeg.org/FFmpeg/FFmpeg/pulls/25694'
  - url: >-
      https://github.com/FFmpeg/FFmpeg/commit/fb13409aaffc151f602ad357db46052e98ea46e8
    label: Patch Commit
  - url: 'https://github.com/FFmpeg/FFmpeg/blob/n9.0.2/libavcodec/adpcmenc.c#L785'
  - url: 'https://github.com/FFmpeg/FFmpeg'
  - url: >-
      https://www.vulncheck.com/advisories/ffmpeg-through-9.0.2-uninitialized-memory-disclosure-via-adpcm-ms-trellis-encoding
    label: >-
      VulnCheck Advisory: FFmpeg through 9.0.2 Uninitialized Memory Disclosure
      via ADPCM_MS Trellis Encoding
tags:
  - cve.org
ingestedAt: '2026-11-09T19:18:02.602Z'
---

## Overview

FFmpeg through 9.0.2 contains an uninitialized memory disclosure vulnerability in adpcm_encode_frame() in libavcodec/adpcmenc.c that leaks heap bytes when encoding mono ADPCM_MS audio with trellis enabled. Attackers submitting audio to a service using this encoding receive output packets where about half of each block contains stale heap memory from the encoding process.

## Affected

- `FFmpeg <= 9.0.2`

## Remediation

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