---
id: "CVE-2026-120244"
kind: "vulnerability"
aliases: ["CVE-2026-120244"]
title: "FFmpeg: truncated PCX image leaks heap memory into decoded pixels"
severity: "medium"
cvss: 6.8
epss: null
exploited: false
status: "open"
category: "package"
products: []
ecosystems: []
tags: ["ffmpeg", "image-upload", "media-processing", "package"]
not_affected_if: ["no-untrusted-pcx-input"]
published_at: "2026-11-01T01:17:17+00:00"
first_seen_at: "2026-11-01T01:47:20+00:00"
updated_at: "2026-11-01T01:47:42+00:00"
sources: [{"source": "nvd", "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-120244", "first_seen_at": "2026-11-01T01:47:20+00:00"}]
---

# FFmpeg: truncated PCX image leaks heap memory into decoded pixels

FFmpeg's PCX decoder copies uninitialized heap memory into the output image when an RLE scanline ends early. An attacker who supplies a crafted PCX file can read leftover heap contents in the decoded picture.

_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`; the sources cover versions 2.1 through 9.0.2.
- Find out whether the service decodes untrusted PCX images, for example with `ffmpeg -i upload.pcx`.

## Timeline

- 2026-11-01T01:47:20+00:00 nvd https://nvd.nist.gov/vuln/detail/CVE-2026-120244

## From the sources

FFmpeg 2.1 through 9.0.2 contains a use of uninitialized resource vulnerability in the PCX decoder that allows attackers to leak heap memory through truncated RLE scanlines. Attackers can craft a PCX image whose RLE data ends early, causing pcx_decode_frame() to copy uninitialized av_malloc() buffer contents into visible decoded pixels.

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_Free to read at a human pace. An API with keys and an MCP server are in preparation; early access: hello@infrastack.ai_