---
id: "CVE-2026-120210"
kind: "vulnerability"
aliases: ["CVE-2026-120210"]
title: "FFmpeg: crafted IMF package lets attackers open files outside the package"
severity: "medium"
cvss: 5.3
epss: null
exploited: false
status: "open"
category: "runtime"
products: []
ecosystems: []
tags: ["ffmpeg", "media-processing", "runtime", "self-hosted"]
not_affected_if: ["no-imf-input", "trusted-input-only"]
published_at: "2026-10-31T18:17:09+00:00"
first_seen_at: "2026-10-31T18:37:13+00:00"
updated_at: "2026-10-31T18:40:39+00:00"
sources: [{"source": "nvd", "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-120210", "first_seen_at": "2026-10-31T18:37:13+00:00"}]
---

# FFmpeg: crafted IMF package lets attackers open files outside the package

FFmpeg's IMF demuxer trusts file paths listed in an ASSETMAP without checking them, so a crafted package can point at files outside its folder. An attacker can read local MXF files, probe whether files exist and how large they are, or make the server issue requests.

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

## How to check

- Check the installed version with `ffmpeg -version`; affected releases are 5.0 through 9.0.2.
- Find out whether the IMF demuxer is used on untrusted input, for example when media packages from users or external partners are processed.

## Fix

- FFmpeg `9.0.2` and earlier in the range 5.0 through 9.0.2 are affected; the sources do not name the fixed version.

## Timeline

- 2026-10-31T18:37:13+00:00 nvd https://nvd.nist.gov/vuln/detail/CVE-2026-120210

## From the sources

FFmpeg 5.0 through 9.0.2 contains a path traversal vulnerability in the IMF demuxer that allows attackers to open files outside the package via unvalidated ASSETMAP Path elements. Attackers can supply a crafted IMF package with '..' or absolute paths to demux local MXF files, probe file existence and size, or trigger server-side requests.

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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_