---
id: CVE-2026-96611
title: FFmpeg before 9.0 has a signed integer overflow in libavformat/mov.c
summary: >-
  FFmpeg before 9.0 has a signed integer overflow in libavformat/mov.c. In
  mov_read_ispe(), uint32_t width/height values from a crafted HEIF ispe box are
  stored into signed int fields without bounds checking, allowing values
  exceeding INT_…
severity: medium
cvss: 6.9
cvssVector: 'CVSS:3.1/AV:L/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:L'
cwe:
  - CWE-190
vendor: FFmpeg
product: FFmpeg
affected:
  - FFmpeg < 9.0
published: '2026-09-23'
updated: '2026-09-24'
sourceUpdated: '2026-09-24T21:00:46.893'
source: NVD
sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2026-96611'
references:
  - url: >-
      https://code.ffmpeg.org/FFmpeg/FFmpeg/commit/059eb2e853c1f62b8df1b73be9318061a7a21b0b
    label: cve@mitre.org
  - url: 'https://code.ffmpeg.org/FFmpeg/FFmpeg/pulls/23455'
    label: cve@mitre.org
  - url: >-
      https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-96611.json
  - url: 'https://access.redhat.com/security/cve/CVE-2026-96611'
  - url: 'https://bugzilla.redhat.com/show_bug.cgi?id=2539442'
  - url: 'https://www.cve.org/CVERecord?id=CVE-2026-96611'
  - url: 'https://nvd.nist.gov/vuln/detail/CVE-2026-96611'
tags:
  - nvd
  - cve.org
  - csaf
  - vex
  - red-hat
epss: 0.00115
epssPercentile: 0.0136
scores:
  nvd: 6.9
  vendor: 6.5
ingestedAt: '2026-09-23T14:25:29.807Z'
---

## Overview

FFmpeg before 9.0 has a signed integer overflow in libavformat/mov.c. In mov_read_ispe(), uint32_t width/height values from a crafted HEIF ispe box are stored into signed int fields without bounds checking, allowing values exceeding INT_MAX to become negative. In read_image_grid(), accumulating these values causes signed integer overflow (undefined behavior per C17 section 6.5), which on x86 wraps to a small positive value, bypassing downstream validity checks.

## Remediation

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

## Vendor advisories

- **Red Hat VEX** · Moderate · affected: Red Hat Enterprise Linux AI (RHEL AI) 3, Red Hat OpenShift AI (RHOAI) · no fix planned: Red Hat Enterprise Linux AI (RHEL AI) 3, Red Hat OpenShift AI (RHOAI) · updated 2026-09-24 · [vex](https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-96611.json)