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CVE-2026-100807: Vulnerability in Mozilla Firefox

0
High
VulnerabilityCVE-2026-100807cvecve-2026-100807
Published: 09/29/2026 (09/29/2026, 12:36:22 UTC)
Source: CVE Database V5
Vendor/Project: Mozilla
Product: Firefox

Description

Privilege escalation in the DOM: Service Workers component. This vulnerability was fixed in Firefox ESR 153.4, Firefox 157, and Firefox ESR 140.17.

CVSS v3.1

Score 8.8high

Attack Vector
Network
Attack Complexity
Low
Privileges Required
None
User Interaction
Required
Scope
Unchanged
Confidentiality
High
Integrity
High
Availability
High
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H

Affected software

Mozilla

Firefox

GitHub Actionsmore threats →ai
mozilla/firefox
pkg:github/mozilla/firefox
Affected versions
<153.4<157<140.17

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AI-Powered Analysis

Machine-generated threat intelligence

AILast updated: 09/29/2026, 13:17:38 UTC

Technical Analysis

This vulnerability involves privilege escalation within the DOM's Service Workers component in Mozilla Firefox. It was addressed and fixed in Firefox ESR 153.4, Firefox 157, and Firefox ESR 140.17. The vendor advisory lists this as a high impact issue and includes it among multiple security vulnerabilities resolved in the specified Firefox versions.

Potential Impact

The vulnerability allows privilege escalation in the browser, which could enable an attacker to gain higher privileges than intended within the Firefox environment. This could potentially lead to unauthorized actions or access within the browser context. The vendor rates the impact as high.

Mitigation Recommendations

A fix is available and has been released in Firefox ESR 153.4, Firefox 157, and Firefox ESR 140.17. Users and administrators should update to these versions or later to remediate this vulnerability.

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Technical Details

Data Version
5.2
Assigner Short Name
mozilla
Date Reserved
2026-09-26T19:18:01.257Z
State
PUBLISHED
Vendor Advisory Urls
[{"url":"https://www.mozilla.org/security/advisories/mfsa2026-100/","vendor":"Mozilla"},{"url":"https://www.mozilla.org/security/advisories/mfsa2026-97/","vendor":"Mozilla"},{"url":"https://www.mozilla.org/security/advisories/mfsa2026-99/","vendor":"Mozilla"}]

Threat ID: 6abbb3f5f7a7c541066409ae

Added to database: 09/29/2026, 12:49:57 UTC

Last enriched: 09/29/2026, 13:17:38 UTC

Last updated: 09/29/2026, 18:20:13 UTC

Views: 6

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