Main Vulnerability Database Vulnerabilities #VU146628

Information disclosure in Mozilla Firefox and Firefox for Android - CVE-2026-84127

Published: September 1, 2026

Vulnerability identifier: #VU146628

CSH Severity: Low

CVSS v4: 5.3 [CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N]

CVE-ID: CVE-2026-84127

CWE-ID: CWE-200

Exploitation vector: Remote access

Exploit availability: No public exploit available

Vulnerability details

The vulnerability allows a remote user to disclose sensitive information.

The vulnerability exists due to improper access control in the WebExtensions component when interacting with extension functionality. A remote user can access exposed information to disclose sensitive information.

Affected software

Mozilla Firefox
Firefox for Android

How to mitigate CVE-2026-84127

Install security update from vendor's website.

Mozilla Firefox - update to 155.0
Firefox for Android - update to 155.0

External References

Related Security Bulletins