---
id: CVE-2026-92053
title: 'Privilege escalation in the Graphics: CanvasWebGL component'
summary: >-
  Privilege escalation in the Graphics: CanvasWebGL component. This
  vulnerability was fixed in Firefox 156, Firefox ESR 153.3, Thunderbird 156,
  and Thunderbird 153.3.
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-269
  - CWE-266
vendor: Mozilla
product: Firefox
affected:
  - Firefox
  - Thunderbird
published: '2026-09-15'
updated: '2026-09-16'
sourceUpdated: '2026-09-16T19:34:05.910'
source: NVD
sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2026-92053'
references:
  - url: 'https://bugzilla.mozilla.org/show_bug.cgi?id=2061503'
    label: security@mozilla.org
  - url: 'https://www.mozilla.org/security/advisories/mfsa2026-90/'
    label: security@mozilla.org
  - url: 'https://www.mozilla.org/security/advisories/mfsa2026-93/'
    label: security@mozilla.org
  - url: 'https://www.mozilla.org/security/advisories/mfsa2026-94/'
    label: security@mozilla.org
  - url: 'https://www.mozilla.org/security/advisories/mfsa2026-96/'
    label: security@mozilla.org
  - url: >-
      https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-92053.json
  - url: 'https://access.redhat.com/security/cve/CVE-2026-92053'
  - url: 'https://bugzilla.redhat.com/show_bug.cgi?id=2533738'
  - url: 'https://www.cve.org/CVERecord?id=CVE-2026-92053'
  - url: 'https://nvd.nist.gov/vuln/detail/CVE-2026-92053'
  - url: 'https://www.mozilla.org/security/advisories/mfsa2026-90/#CVE-2026-92053'
  - url: 'https://www.mozilla.org/security/advisories/mfsa2026-94/#CVE-2026-92053'
tags:
  - nvd
  - cve.org
  - csaf
  - vex
  - red-hat
  - score-dispute
ssvc:
  exploitation: none
  automatable: 'no'
  technicalImpact: total
  timestamp: '2026-09-15T13:09:30.759286Z'
ingestedAt: '2026-09-15T12:36:50.181Z'
scores:
  nvd: 8.8
  vendor: 6.1
epss: 0.00262
epssPercentile: 0.18289
---

## Overview

Privilege escalation in the Graphics: CanvasWebGL component. This vulnerability was fixed in Firefox 156, Firefox ESR 153.3, Thunderbird 156, and Thunderbird 153.3.

## Remediation

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

## Vendor advisories

- **Red Hat VEX** · Moderate · updated 2026-09-17 · [vex](https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-92053.json)