CVE-2026-6145

User Registration & Membership <= 5.1.5 - Unauthenticated Missing Authorization to Admin Approval Bypass via 'action' Parameter

2026-05-13 19:52
Anthony Cihan (Hann1bl3L3ct3r)

Strategic Overview

Status
Patched in 5.1.6
Affected Plugin
User Registration & Membership – Free & Paid Memberships, Subscriptions, Content Restriction, User Profile, Custom User Registration & Login Builder
Affected Version
<= 5.1.5
CVSS
5.3Medium
Weakness type
CWE-862 · Missing Authorization
CVE
CVE-2026-6145
View all User Registration & Membership – Free & Paid Memberships, Subscriptions, Content Restriction, User Profile, Custom User Registration & Login Builder vulnerabilities

At a glance

CVE-2026-6145 is a medium-severity Missing Authorization vulnerability in the User Registration & Membership WordPress plugin, affecting versions <= 5.1.5. It carries a CVSS score of 5.3 (reachable over the network; low attack complexity). Exploitation requires no authentication. The issue is fixed in version 5.1.6; sites on affected versions should update now. Disclosed May 2026, reported by Anthony Cihan (Hann1bl3L3ct3r).

Vulnerability Overview

The User Registration & Membership plugin for WordPress is vulnerable to Missing Authorization in all versions up to, and including, 5.1.5. This is due to the is_admin_creation_process() method relying solely on the presence of action=createuser in the $_REQUEST superglobal without performing any authentication or capability check. This makes it possible for unauthenticated attackers to bypass the admin approval requirement when registering new accounts via the fallback submission path.

Technical Analysis

The vector marks this flaw as remotely reachable over the network, with low attack complexity — no special timing or configuration is needed, and no privileges on the target site, and no interaction from a victim user.

CWE-862: Missing Authorization

User Registration & Membership <= 5.1.5 carries this weakness at is_admin_creation_process(), and reaching it takes no account at all. A missing authorization check means a function is reachable by anyone who can reach the endpoint, because the code never asks whether the caller is allowed to perform the action.

Any user who can reach the endpoint gets to run an action reserved for higher-privileged roles, from reading protected data to changing settings or content. For User Registration & Membership the fix is 5.1.6: builds <= 5.1.5 are affected, anything from 5.1.6 onward is not.

Remediation

Update to version 5.1.6, or a newer patched version

How does WordSec protect against this?

This one needs no account at all, which puts it outside what login hardening can reach; WordSec's login security narrows the account-level paths around it, and the firewall is what inspects the request itself. None of that substitutes for the fix: User Registration & Membership 5.1.6 closes this, and updating the plugin is the step that ends it.

  • Login Security
  • Alerts

External References

https://www.cve.org/CVERecord?id=CVE-2026-6145https://www.wordfence.com/threat-intel/vulnerabilities/id/b6b349f2-24c9-4921-bb5f-a7726ebc5c2ahttps://nvd.nist.gov/vuln/detail/CVE-2026-6145

Related records

Other vulnerabilities in User Registration & Membership – Free & Paid Memberships, Subscriptions, Content Restriction, User Profile, Custom User Registration & Login Builder

Vulnerability data © Defiant, Inc., provided under the Wordfence Intelligence T&C