CVE-2025-4334

Simple User Registration <= 6.3 - Unauthenticated Privilege Escalation

2025-06-25 13:47

Strategic Overview

Status: Patched in 6.4
Affected Plugin: MemberHero – Simple User Registration & Login
Affected Version: <= 6.3
CVSS: 9.8Critical
Weakness type: CWE-269 · Improper Privilege Management
CVE: CVE-2025-4334

View all MemberHero – Simple User Registration & Login vulnerabilities

At a glance

CVE-2025-4334 is a critical-severity Improper Privilege Management vulnerability in the MemberHero WordPress plugin, affecting versions <= 6.3. It carries a CVSS score of 9.8 (reachable over the network; low attack complexity; high confidentiality, integrity, availability impact). Exploitation requires no authentication. The issue is fixed in version 6.4; sites on affected versions should update now. Disclosed June 2025, reported by Chuck.

Vulnerability Overview

The Simple User Registration plugin for WordPress is vulnerable to Privilege Escalation in all versions up to, and including, 6.3. This is due to insufficient restrictions on user meta values that can be supplied during registration. This makes it possible for unauthenticated attackers to register as an administrator.

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. A successful exploit has high impact on confidentiality, integrity, availability — full site compromise territory.

CWE-269: Improper Privilege Management

Reaching this weakness in MemberHero <= 6.3 takes no account at all. Improper privilege management means the code lets an account end up with capabilities its role should not have.

It converts a low-privileged account into an administrative one, which makes every other restriction on the site irrelevant. For MemberHero the fix is 6.4: builds <= 6.3 are affected, anything from 6.4 onward is not.

Remediation

Update to version 6.4, 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: MemberHero 6.4 closes this, and updating the plugin is the step that ends it.

Login Security
Alerts

External References

https://www.cve.org/CVERecord?id=CVE-2025-4334 https://www.wordfence.com/threat-intel/vulnerabilities/id/c211e0c0-3086-43d2-853c-489f9c42b0ab https://nvd.nist.gov/vuln/detail/CVE-2025-4334

Related records

Same weakness class

Other vulnerabilities in MemberHero – Simple User Registration & Login

CVSS Vector

9.8

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

Base

Attack VectorNetwork
Attack ComplexityLow
Privileges RequiredNone
User InteractionNone
ScopeUnchanged
ConfidentialityHigh
IntegrityHigh
AvailabilityHigh

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