CVE-2026-74959: firefox: thunderbird: Mitigation bypass in the Storage: Cache API component

Severity: Critical

CVSS Score: 9.1

Mitigation bypass in the Storage: Cache API component. This vulnerability was fixed in Firefox 154, Firefox ESR 140.14, Firefox ESR 153.1, Thunderbird 154, Thunderbird 140.14, and Thunderbird 153.1.