Privilege Escalation in Firefox Application Update Component
CVE-2026-109704

8.8HIGH

Key Information:

Vendor

Mozilla
Status
Firefox
Thunderbird
Vendor
CVE Published:
13 October 2026

What is CVE-2026-109704?

A privilege escalation vulnerability in the Application Update component of Firefox could allow unauthorized access if exploited. Mozilla has addressed this issue in the latest versions, including Firefox 158 and Firefox ESR 153.5, ensuring users are protected. It is critical for users to update their browsers promptly to maintain security against potential exploits.

Affected Version(s)

Firefox 153.5

Firefox 158

Thunderbird 153.5

References

https://bugzilla.mozilla.org/show_bug.cgi?id=2037979
https://www.mozilla.org/security/advisories/mfsa2026-106/
https://www.mozilla.org/security/advisories/mfsa2026-108/

CVSS V3.1

Score:
8.8
Severity:
HIGH
Confidentiality:
High
Integrity:
High
Availability:
High
Attack Vector:
Network
Attack Complexity:
Low
Privileges Required:
Low
User Interaction:
None
Scope:
Unchanged

Timeline

  • Vulnerability published

  • Vulnerability Reserved

Credit

Noel
.