CVE-2026-76581
CriticalCVSS 9.8Summary
The WPMU DEV Dashboard plugin for WordPress up to version 5.0.1 is vulnerable to Authentication Bypass due to inconsistent HMAC message construction between the `wdpsso_step1` and `wdpsso_step2` AJAX actions. An unauthenticated attacker can obtain a valid HMAC from step 1 and replay it to step 2, resulting in an authenticated administrator session.
Risk Assessment
An attacker can take over an administrator session, leading to full compromise of the WordPress site.
Recommendation
Update the plugin to a patched version and disable Hub SSO if not essential.
Original NVD description (English source)
The WPMU DEV Dashboard plugin for WordPress is vulnerable to Authentication Bypass in all versions up to, and including, 5.0.1. This is due to inconsistent and ambiguous HMAC message construction between the unauthenticated `wdpsso_step1` and `wdpsso_step2` AJAX actions, where step 1 signs and discloses an unseparated concatenation of the token, state, redirect, and domain values, while step 2 verifies an unseparated concatenation that omits the domain field. This makes it possible for unauthenticated attackers, on sites connected to WPMU DEV with Hub SSO enabled and mapped to an administrator, to obtain a valid HMAC from step 1 and replay it to step 2 by moving the domain value into the redirect field, resulting in an authenticated administrator session.