CVE-2026-109739
Received Received - Intake

Privilege Escalation in Firefox WebExtensions

Publication date: 2026-10-13

Last updated on: 2026-10-13

Assigner: Mozilla Corporation

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

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Meta Information

Published
2026-10-13
Last Modified
2026-10-13
Generated
2026-10-13
AI Q&A
2026-10-13
EPSS Evaluated
N/A
NVD
CVE-2026-109739
EUVD
EUVD-2026-98501

Affected Vendors & Products

Showing 1 associated CPE
Vendor Product Version / Range
mozilla firefox 158

Helpful Resources

Exploitability

CWE
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KEV
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CWE ID Description
CWE-UNKNOWN

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Executive Summary

This is a privilege escalation vulnerability in the WebExtensions component of Firefox. It allows an attacker with limited access to gain higher privileges within the browser. The issue was resolved in Firefox version 158.

Impact Analysis

If exploited, this vulnerability could let an attacker perform actions they are not authorized to do, such as accessing sensitive data or installing malicious extensions. Users running vulnerable Firefox versions are at risk.

Mitigation Strategies

Update Firefox to version 158 or later to address the privilege escalation vulnerability in the WebExtensions component.

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