---
id: CVE-2026-109739
title: Privilege escalation in the WebExtensions component
summary: >-
  Privilege escalation in the WebExtensions component. This vulnerability was
  fixed in Firefox 158.
severity: none
published: '2026-10-13'
updated: '2026-10-13'
sourceUpdated: '2026-10-13T16:18:13.247'
source: NVD
sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2026-109739'
references:
  - url: 'https://bugzilla.mozilla.org/show_bug.cgi?id=2049069'
    label: security@mozilla.org
  - url: 'https://www.mozilla.org/security/advisories/mfsa2026-106/'
    label: security@mozilla.org
tags:
  - nvd
ingestedAt: '2026-10-13T13:27:04.003Z'
---

## Overview

Privilege escalation in the WebExtensions component. This vulnerability was fixed in Firefox 158.

## Remediation

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