---
id: CVE-2026-100782
title: >-
  Privilege escalation due to incorrect boundary conditions in the Graphics
  component
summary: >-
  Privilege escalation due to incorrect boundary conditions in the Graphics
  component. This vulnerability was fixed in Firefox ESR 153.4, Thunderbird 157,
  Thunderbird 140.17, Thunderbird 153.4, Firefox 157, Firefox ESR 115.42, and
  Firefox …
severity: high
cvss: 8.8
cvssVector: 'CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H'
cwe:
  - CWE-119
vendor: mozilla
product: firefox
affected:
  - firefox < 115.42.0
  - 'firefox >= 116.0, < 140.17.0'
  - 'firefox >= 141.0, < 153.4.0'
  - 'firefox >= 154.0.0, < 157.0.0'
  - thunderbird < 140.17.0
  - 'thunderbird >= 141.0, < 153.4.0'
  - 'thunderbird >= 154.0, < 157.0'
patched:
  - firefox 157.0.0
  - thunderbird 157.0
published: '2026-09-29'
updated: '2026-10-05'
sourceUpdated: '2026-10-05T13:50:14.003'
source: NVD
sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2026-100782'
references:
  - url: 'https://bugzilla.mozilla.org/show_bug.cgi?id=2068456'
    label: security@mozilla.org
  - url: 'https://www.mozilla.org/security/advisories/mfsa2026-100/'
    label: security@mozilla.org
  - url: 'https://www.mozilla.org/security/advisories/mfsa2026-101/'
    label: security@mozilla.org
  - url: 'https://www.mozilla.org/security/advisories/mfsa2026-102/'
    label: security@mozilla.org
  - url: 'https://www.mozilla.org/security/advisories/mfsa2026-103/'
    label: security@mozilla.org
  - url: 'https://www.mozilla.org/security/advisories/mfsa2026-97/'
    label: security@mozilla.org
  - url: 'https://www.mozilla.org/security/advisories/mfsa2026-98/'
    label: security@mozilla.org
  - url: 'https://www.mozilla.org/security/advisories/mfsa2026-99/'
    label: security@mozilla.org
  - url: >-
      https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-100782.json
  - url: 'https://access.redhat.com/security/cve/CVE-2026-100782'
  - url: 'https://bugzilla.redhat.com/show_bug.cgi?id=2543152'
  - url: 'https://www.cve.org/CVERecord?id=CVE-2026-100782'
  - url: 'https://nvd.nist.gov/vuln/detail/CVE-2026-100782'
  - url: 'https://www.mozilla.org/security/advisories/mfsa2026-102/#CVE-2026-100782'
  - url: 'https://www.mozilla.org/security/advisories/mfsa2026-99/#CVE-2026-100782'
  - url: 'https://access.redhat.com/errata/RHSA-2026:85240'
  - url: 'https://access.redhat.com/errata/RHSA-2026:76764'
  - url: 'https://access.redhat.com/errata/RHSA-2026:80674'
  - url: 'https://access.redhat.com/errata/RHSA-2026:76850'
  - url: 'https://access.redhat.com/errata/RHSA-2026:85243'
  - url: 'https://access.redhat.com/errata/RHSA-2026:85242'
  - url: 'https://access.redhat.com/errata/RHSA-2026:85241'
  - url: 'https://access.redhat.com/errata/RHSA-2026:85244'
  - url: 'https://access.redhat.com/errata/RHSA-2026:76761'
  - url: 'https://access.redhat.com/errata/RHSA-2026:80694'
tags:
  - nvd
  - cve.org
  - csaf
  - vex
  - red-hat
epss: 0.00259
epssPercentile: 0.17438
ssvc:
  exploitation: none
  automatable: 'no'
  technicalImpact: total
  timestamp: '2026-09-29T13:16:23.464963Z'
ingestedAt: '2026-09-29T13:34:31.662Z'
scores:
  nvd: 8.8
  vendor: 7.5
---

## Overview

Privilege escalation due to incorrect boundary conditions in the Graphics component. This vulnerability was fixed in Firefox ESR 153.4, Thunderbird 157, Thunderbird 140.17, Thunderbird 153.4, Firefox 157, Firefox ESR 115.42, and Firefox ESR 140.17.

## Affected

- `firefox < 115.42.0`
- `firefox >= 116.0, < 140.17.0`
- `firefox >= 141.0, < 153.4.0`
- `firefox >= 154.0.0, < 157.0.0`
- `thunderbird < 140.17.0`
- `thunderbird >= 141.0, < 153.4.0`
- `thunderbird >= 154.0, < 157.0`

## Remediation

Upgrade past the affected range:

- `firefox 157.0.0`
- `thunderbird 157.0`

## Vendor advisories

- **Red Hat VEX** · Important · affected: Red Hat Enterprise Linux 10, Red Hat Enterprise Linux 6, Red Hat Enterprise Linux 7, Red Hat Enterprise Linux 8 · no fix planned: Red Hat Enterprise Linux 6, Red Hat Enterprise Linux 7, Red Hat Enterprise Linux 10, Red Hat Enterprise Linux 8 · updated 2026-10-23 · [vex](https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-100782.json)
- **RHSA-2026:85240** · Red Hat · fixed in: Red Hat Enterprise Linux AppStream EUS (v. 10.0) · released 2026-10-19 · [advisory](https://access.redhat.com/errata/RHSA-2026:85240)
- **RHSA-2026:76764** · Red Hat · fixed in: Red Hat Enterprise Linux AppStream (v. 10) · released 2026-10-06 · [advisory](https://access.redhat.com/errata/RHSA-2026:76764)
- **RHSA-2026:80674** · Red Hat · fixed in: Red Hat Enterprise Linux AppStream (v. 10) · released 2026-10-12 · [advisory](https://access.redhat.com/errata/RHSA-2026:80674)
- **RHSA-2026:76850** · Red Hat · fixed in: Red Hat Enterprise Linux AppStream (v. 8) · released 2026-10-06 · [advisory](https://access.redhat.com/errata/RHSA-2026:76850)
- **RHSA-2026:85243** · Red Hat · fixed in: Red Hat Enterprise Linux AppStream AUS (v.8.4), Red Hat Enterprise Linux AppStream EUS EXTENSION (v.8.4) · released 2026-10-19 · [advisory](https://access.redhat.com/errata/RHSA-2026:85243)
- **RHSA-2026:85242** · Red Hat · fixed in: Red Hat Enterprise Linux AppStream E4S (v.9.2) · released 2026-10-19 · [advisory](https://access.redhat.com/errata/RHSA-2026:85242)
- **RHSA-2026:85241** · Red Hat · fixed in: Red Hat Enterprise Linux AppStream E4S (v.9.4) · released 2026-10-19 · [advisory](https://access.redhat.com/errata/RHSA-2026:85241)
- **RHSA-2026:85244** · Red Hat · fixed in: Red Hat Enterprise Linux AppStream EUS (v.9.6) · released 2026-10-19 · [advisory](https://access.redhat.com/errata/RHSA-2026:85244)
- **RHSA-2026:76761** · Red Hat · fixed in: Red Hat Enterprise Linux AppStream (v. 9) · released 2026-10-08 · [advisory](https://access.redhat.com/errata/RHSA-2026:76761)
- **RHSA-2026:80694** · Red Hat · fixed in: Red Hat Enterprise Linux AppStream (v. 9) · released 2026-10-12 · [advisory](https://access.redhat.com/errata/RHSA-2026:80694)
