CVE-2026-11883 is an improper authentication vulnerability (CWE-287) in the WebAuthn Provider for Two Factor WordPress plugin. Versions prior to 2.5.6 do not correctly validate the second-factor authentication response, enabling an attacker with knowledge of a user's password to bypass the two-factor authentication mechanism by submitting a malformed request. This flaw undermines the intended security of two-factor authentication, potentially allowing unauthorized access to user accounts.

Successful exploitation allows an attacker who already knows a user's password to bypass the two-factor authentication requirement, resulting in full compromise of the user's account. The vulnerability impacts confidentiality, integrity, and availability of the affected accounts, as indicated by the CVSS vector (C:H/I:H/A:H).

Patch status is not yet confirmed — check the vendor advisory for current remediation guidance. Until an official fix is available, users should consider additional protective measures such as monitoring for suspicious login activity and restricting password knowledge exposure. Avoid relying solely on the affected plugin's two-factor authentication for security.