CVE-2026-74979

CriticalCVSS 9.8/10Last modified Aug 20, 2026

Description

Mitigation bypass in the Add-ons Manager component. This vulnerability was fixed in Firefox 154, Firefox ESR 153.1, Thunderbird 154, and Thunderbird 153.1.

Metrics

CVSS 3.1 9.8/10CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

Weakness enumeration

CWE-284

Affected software

No affected versions have been published.

Timeline

Published: Aug 18, 2026
Last modified: Aug 20, 2026
NVD status: Analyzed

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