---
title: "CVE-2026-66037\n    | Ubuntu"
description: Ubuntu is an open source software operating system that runs from the
  desktop, to the cloud, to all your internet connected things.
url: https://ubuntu.com/security/CVE-2026-66037?format=md
keywords: index, follow
---

# CVE-2026-66037

Publication date 24 July 2026

Last updated 7 August 2026

---

Ubuntu priority

**Medium**

[Why this priority?](https://ubuntu.com/security/cves/about#priority )

## Cvss 3 Severity Score

**6.5 · Medium**

[Score breakdown](https://ubuntu.com/security/CVE-2026-66037?format=md#impact-score)

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## Description

FFmpeg through 8.1.2, fixed in commit 5d7112c, contains an uncontrolled
resource consumption vulnerability in the IAMF demuxer that allows an
unauthenticated attacker to cause multi-gigabyte memory allocation from a
17-byte input file by supplying a crafted count\_label field. The
mix\_presentation\_obu() function in libavformat/iamf\_parse.c calls
av\_calloc(count\_label, sizeof(\*language\_label)) with an attacker-controlled
value before validating available OBU data, enabling an allocation
amplification of approximately 126 million bytes per input byte that
exhausts process memory or triggers an OOM-kill during format probing.

## Status

Show unmaintained releases

| Package | Ubuntu Release | Status |
| --- | --- | --- |
| ffmpeg | 26.04 LTS resolute | Vulnerable |
| 24.04 LTS noble | Not affected |
| 22.04 LTS jammy | Not affected |
| 20.04 LTS focal | Not affected |
| 18.04 LTS bionic | Not affected |
| 16.04 LTS xenial | Not affected |
| libav | 26.04 LTS resolute | Not in release |
| 24.04 LTS noble | Not in release |
| 22.04 LTS jammy | Not in release |
| 14.04 LTS trusty | Not affected |

---

* [How can I get the fixes?](https://ubuntu.com/security/cves/about#security)
* [What do statuses mean?](https://ubuntu.com/security/cves/about#statuses)

## Severity score breakdown

CVSS version:

CVSS v4.0

[CVSS v4.0](https://ubuntu.com/security/CVE-2026-66037?format=md)
[CVSS v3.0](https://ubuntu.com/security/CVE-2026-66037?format=md)

**Base score**

7.1 · High

* Base metrics

  | Parameter | Value |
  | --- | --- |
  | Attack vector | Network |
  | Attack complexity | Low |
  | Attack requirements | None |
  | Privileges required | None |
  | User interaction | Passive |
  | Vulnerable system - Confidentiality impact | None |
  | Vulnerable system - Integrity impact | None |
  | Vulnerable system - Availability impact | High |
  | Subsequent system - Confidentiality impact | None |
  | Subsequent system - Integrity impact | None |
  | Subsequent system - Availability impact | None |
* Scores

  | Parameter | Value |
  | --- | --- |
  | Base score | 7.1 · High |
  | Base + Threat score | - |
  | Base + Environmental score | - |
  | Base + Threat + Environmental score | - |

**Vector:** CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N

## References

* [MITRE](https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2026-66037)
* [NVD](https://nvd.nist.gov/vuln/detail/CVE-2026-66037)
* [Launchpad](https://launchpad.net/bugs/cve/CVE-2026-66037)
* [Debian](https://security-tracker.debian.org/tracker/CVE-2026-66037)

### Other references

* <https://www.cve.org/CVERecord?id=CVE-2026-66037>
* <https://code.ffmpeg.org/FFmpeg/FFmpeg/pulls/23627>
* <https://code.ffmpeg.org/FFmpeg/FFmpeg/commit/86708357d126af84c16f80d9c57335d1e8c845c5>
* <https://www.vulncheck.com/advisories/ffmpeg-iamf-demuxer-uncontrolled-resource-consumption-via-mix-presentation-obu>