CVE-2026-8961

Spoofing issue in the Form Autofill component

State: Published
Severity: 6.5 Medium
Published: May 19, 2026
Updated: May 20, 2026
Reserved: May 19, 2026

Description

Spoofing issue in the Form Autofill component. This vulnerability was fixed in Firefox 151, Firefox ESR 140.11, Thunderbird 151, and Thunderbird 140.11.

Scores

CVSS	Score	Vector	Source
3.1	6.5 Medium	CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:H/A:N	CISA-ADP

Weaknesses

CWE-290 Authentication Bypass by Spoofing

Affected Products

Product	Versions
FirefoxMozilla	140.11 through 140.*Not affected 151 and laterNot affected
ThunderbirdMozilla	140.11 through 140.*Not affected 151 and laterNot affected

References

https://bugzilla.mozilla.org/show_bug.cgi?id=1962625
https://www.mozilla.org/security/advisories/mfsa2026-46/
https://www.mozilla.org/security/advisories/mfsa2026-48/
https://www.mozilla.org/security/advisories/mfsa2026-50/
https://www.mozilla.org/security/advisories/mfsa2026-51/

Every record here comes from the CVE Program’s CVE List. © 1999–2026 The MITRE Corporation. CVE is a registered trademark of The MITRE Corporation. The records are reproduced under the CVE Program terms of use.