WPMU DEV Dashboard <= 5.0.1 - Authentication Bypass to Administrator via SSO HMAC Canonicalization Confusion
| CVE | CVE-2026-76581 |
|---|---|
| CVSS | 9.8 (Critical) |
| Publicly Published | August 27, 2026 |
| Last Updated | August 28, 2026 |
| Researchers |
Alex Thomas
- Wordfence
Wordfence Argus - Wordfence |
Description
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.
Wordfence blocked 54 attacks targeting this vulnerability in the past 24 hours.
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Vulnerability Details for WPMU DEV Dashboard
| Software Type | Plugin |
|---|---|
| Software Slug | wpmudev-updates |
| Patched? | Yes |
| Remediation | Update to version 5.0.2, or a newer patched version |
| Affected Version |
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| Patched Version |
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Recent vulnerabilities in WPMU DEV Dashboard
| # | Title | CVE ID | CVSS | Researchers | Date |
|---|---|---|---|---|---|
| 1 | WPMU DEV Dashboard <= 5.0.0 - Authentication Bypass to Arbitrary Plugin Installation (Remote Code Execution) via Forged WDP_AUTH HMAC on ?wpmudev-hub= Endpoint | CVE-2026-15459 | Austin Ginder | August 5, 2026 |
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