---
id: CVE-2025-55640
title: >-
  A heap buffer overflow in the stbl_AddSize function (isomedia/stbl_write.c) of
  GPAC MP4Box v2.4 allows attackers to cause a Denial of Service (DoS) via
  supplying a crafted MP4 file.
summary: >-
  A heap buffer overflow in the stbl_AddSize function (isomedia/stbl_write.c) of
  GPAC MP4Box v2.4 allows attackers to cause a Denial of Service (DoS) via
  supplying a crafted MP4 file.
severity: medium
cvss: 5.5
cvssVector: 'CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H'
cvssSource: adp
ssvc:
  exploitation: poc
  automatable: 'no'
  technicalImpact: partial
  timestamp: '2026-10-26T17:25:53.826480Z'
exploitAvailable: true
published: '2026-10-16'
updated: '2026-10-26'
sourceUpdated: '2026-10-26T17:26:18.665Z'
source: CVEORG
sourceUrl: 'https://www.cve.org/CVERecord?id=CVE-2025-55640'
references:
  - url: 'https://github.com/gpac/gpac/issues/3261'
  - url: 'https://github.com/sigdevel/pocs/blob/main/res/gpac/MP4Box/25/25_poc.mp4'
  - url: >-
      https://github.com/gpac/gpac/commit/321624f28d19a413449fd1718d1eb59037f8f7fc
  - url: 'https://infosec.exchange/@sigdevel/116769271709415444'
tags:
  - cve.org
  - exploit-available
epss: 0.00195
epssPercentile: 0.09149
ingestedAt: '2026-10-16T18:43:08.628Z'
---

## Overview

A heap buffer overflow in the stbl_AddSize function (isomedia/stbl_write.c) of GPAC MP4Box v2.4 allows attackers to cause a Denial of Service (DoS) via supplying a crafted MP4 file.

## Remediation

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