CVE-2026-74959

CriticalCVSS 9.1/10Last modified Aug 24, 2026

Description

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.

Metrics

CVSS 3.1 9.1/10CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N

Weakness enumeration

CWE-693

Affected software

VendorProductVersions
MozillaFirefox—
MozillaThunderbird—

References

Timeline

Published
Aug 18, 2026
Last modified
Aug 24, 2026
NVD status
Analyzed

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