CVE-2026-2791

Mitigation bypass in the Networking: Cache component

State: Published
Severity: 9.8 Critical
Published: Feb 24, 2026
Updated: Apr 21, 2026
Reserved: Feb 19, 2026

Description

Mitigation bypass in the Networking: Cache component. This vulnerability was fixed in Firefox 148, Firefox ESR 140.8, Thunderbird 148, and Thunderbird 140.8.

Scores

CVSS	Score	Vector	Source
3.1	9.8 Critical	CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H	CISA-ADP

Weaknesses

CWE-288 Authentication Bypass Using an Alternate Path or Channel

Affected Products

Product	Versions
FirefoxMozilla	140.8 through 140.*Not affected 148 and laterNot affected
ThunderbirdMozilla	140.8 through 140.*Not affected 148 and laterNot affected

References

https://bugzilla.mozilla.org/show_bug.cgi?id=2015220
https://www.mozilla.org/security/advisories/mfsa2026-13/
https://www.mozilla.org/security/advisories/mfsa2026-15/
https://www.mozilla.org/security/advisories/mfsa2026-16/
https://www.mozilla.org/security/advisories/mfsa2026-17/

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