---
id: CVE-2026-125101
title: FFmpeg through 9.0.2 VMnc Decoder Uninitialized Heap Memory Disclosure
summary: >-
  FFmpeg through 9.0.2 contains an information disclosure vulnerability in the
  VMnc decoder in libavcodec/vmnc.c that restores an unwritten cursor save area
  into later frames. Attackers can supply a crafted VMnc stream where a frame
  fails …
severity: low
cvss: 3.3
cvssVector: 'CVSS:3.1/AV:L/AC:L/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: '2026-11-09T19:10:56.303Z'
source: CVEORG
sourceUrl: 'https://www.cve.org/CVERecord?id=CVE-2026-125101'
references:
  - url: 'https://code.ffmpeg.org/FFmpeg/FFmpeg/pulls/25716'
  - url: >-
      https://github.com/FFmpeg/FFmpeg/commit/50865f20b1f474e6b11735c88f668751bc9aa528
    label: Patch Commit
  - url: 'https://github.com/FFmpeg/FFmpeg/blob/n9.0.2/libavcodec/vmnc.c#L348'
  - url: 'https://github.com/FFmpeg/FFmpeg'
  - url: >-
      https://www.vulncheck.com/advisories/ffmpeg-through-9.0.2-vmnc-decoder-uninitialized-heap-memory-disclosure
    label: >-
      VulnCheck Advisory: FFmpeg through 9.0.2 VMnc Decoder Uninitialized Heap
      Memory Disclosure
tags:
  - cve.org
ingestedAt: '2026-11-09T19:18:02.626Z'
---

## Overview

FFmpeg through 9.0.2 contains an information disclosure vulnerability in the VMnc decoder in libavcodec/vmnc.c that restores an unwritten cursor save area into later frames. Attackers can supply a crafted VMnc stream where a frame fails after loading a cursor shape, causing uninitialized heap bytes from screendta to appear in decoded output.

## Affected

- `FFmpeg <= 9.0.2`

## Remediation

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