External risk intelligence

Simple User Registration Authentication Bypass Vulnerability

CVE advisorySeverity: CRITICAL (CVSS 9.8)

CVE-2024-49604

This vulnerability affects a WordPress plugin designed for user registration. Such plugins are typically installed on web servers to manage public-facing user accounts and registration forms, making the vulnerable functionality directly accessible via the public internet as part of standard website operations.

Missing Authentication

Najeebmedia Memberhero

5.5 and earlier

Halo Surface Signal: 4 out of 5 — likely to be public-facing.

External exposure likelihood

Horizon Alert

Summary of the vulnerability and why it matters

This advisory details an Authentication Bypass vulnerability in a WordPress plugin used for user registration, which could allow unauthorized access to user accounts. The primary concern at this time is to confirm if this plugin is in use and, if so, to understand the potential exposure.

Unauthorized account access is possible.
A bypass flaw in user registration.
Confirm relevance and exposure quickly.

Attack Path

How an attacker could exploit the issue

An attacker could bypass authentication by accessing the user registration feature of the Simple User Registration plugin via a web browser. This bypass could allow an attacker to gain administrative access to the WordPress site.

No authentication is required.
Access the registration form.
Gain administrative control.

Live Threat

Current exploitation, exposure, and threat context

This vulnerability in the Simple User Registration plugin could allow an unauthenticated attacker to bypass login mechanisms and gain unauthorized access to user accounts and sensitive information within the WordPress site. This occurs when the plugin is used to manage user registration and an attacker exploits a flaw in the authentication process.

Unauthorized access to user accounts.
Exploiting alternate authentication paths.
Compromise of user data and site integrity.

Operational Fix

Recommended remediation, mitigation, and detection steps

This critical authentication bypass vulnerability in the Simple User Registration plugin requires immediate attention from teams managing WordPress sites, particularly those responsible for application security and infrastructure. The first step is to identify all instances of the plugin, confirm their exposure to the internet, and determine business criticality to prioritize remediation efforts with the accountable application owner.

Ownership: WordPress application and infrastructure teams.
Verify: Plugin presence and internet exposure.
Action: Plan and execute remediation.

Supplementary metadata

CVSS vector

Validate whether this threat affects your internet-facing exposure.

Halo Threat Intelligence helps prioritize remediation with Halo Surface Signal and H/A/L/O context. Start exposure validation with a free external attack surface trial.

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Frequently asked questions

What is the Simple User Registration plugin?

Simple User Registration is a WordPress plugin developed by NajeebMedia, also known as MemberHero. It is primarily used to manage user account creation, allowing visitors to sign up and join a WordPress site. By handling registration forms and account processing, it serves as a gateway for new users to enter the site's ecosystem.

What does this CVE-2024-49604 vulnerability mean?

This vulnerability is an Authentication Bypass using an Alternate Path or Channel (CWE-288). In plain terms, it means the plugin has a logic flaw that lets someone skip the normal login process entirely. Instead of providing valid credentials, an attacker can use this unintended pathway to gain unauthorized access to the site as if they were a legitimate user or even an administrator.

How can an attacker trigger this flaw?

An attacker can trigger this vulnerability by interacting with the registration features of the plugin directly through a web browser. No special authentication or prior permissions are required to initiate the process. It is important to note that this bug is specific to the plugin's registration logic; standard WordPress login forms that do not utilize this plugin's specific registration path are not the mechanism for this bypass.

Is my site at risk if I use this plugin?

According to Halo Surface Signal, because this plugin is designed to handle public-facing registration forms, it is almost certainly exposed to the internet as part of normal operations. This makes the vulnerability highly relevant for any site running the plugin, as it does not require an attacker to be on an internal network to access the registration pathway.

What should I do first to address this?

Begin by auditing your WordPress environment to confirm if the Simple User Registration plugin is installed. Once you have identified all instances, work with your application owners to evaluate the site's business criticality. Your primary goal is to assess whether the plugin is essential and to prepare for necessary security updates or removal to mitigate the risk of unauthorized account access.

References

patchstack.com/database/Wordpress/Plugin/wp-registration/vulnerabili…

Written by Nicholas Merritt

Nicholas Merritt is VP of Security Solutions at Halo Security. With more than 25 years across application security, vulnerability prioritization, and offensive security, he helps teams translate threat data into practical exposure validation and remediation focus. He authors Halo Threat Intelligence CVE advisories using Halo Surface Signal and H/A/L/O context to prioritize internet-facing risk.