Firefox Form Autofill Spoofing CVE-2026-8961 (fixed in 151/ESR 140.11)
CVE-2026-8961 Published on May 19, 2026
Spoofing issue in the Form Autofill component
Spoofing issue in the Form Autofill component. This vulnerability was fixed in Firefox 151, Firefox ESR 140.11, Thunderbird 151, and Thunderbird 140.11.
Vulnerability Analysis
CVE-2026-8961 can be exploited with network access, requires user interaction. This vulnerability is considered to have a low attack complexity. The potential impact of an exploit of this vulnerability is considered to have no impact on confidentiality, a high impact on integrity, and no impact on availability.
Weakness Type
Authentication Bypass by Spoofing
This attack-focused weakness is caused by improperly implemented authentication schemes that are subject to spoofing attacks.
Products Associated with CVE-2026-8961
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Affected Versions
Mozilla Firefox:- Version 140.11, <= 140.* is unaffected.
- Version 151, <= * is unaffected.
- Version 140.11, <= 140.* is unaffected.
- Version 151, <= * is unaffected.