CVE-2024-49604: Simple User Registration Auth Bypass

CVE-2024-49604 Overview

CVE-2024-49604 is an Authentication Bypass Using an Alternate Path or Channel vulnerability affecting the Simple User Registration plugin for WordPress developed by Najeeb Ahmad. This critical security flaw enables attackers to bypass authentication mechanisms entirely, potentially leading to unauthorized account takeover. The vulnerability leverages an alternate authentication path that circumvents standard security controls, allowing malicious actors to gain access to user accounts without valid credentials.

Critical Impact

This vulnerability allows unauthenticated attackers to take over user accounts on WordPress sites running the affected plugin, potentially compromising sensitive user data, administrative access, and the integrity of the entire WordPress installation.

Affected Products

• Simple User Registration plugin for WordPress (versions through 5.5)
• WordPress installations utilizing najeebmedia:simple_user_registration
• Sites with user registration functionality enabled via the vulnerable plugin

Discovery Timeline

• 2024-10-20 - CVE-2024-49604 published to NVD
• 2024-10-23 - Last updated in NVD database

Technical Details for CVE-2024-49604

Vulnerability Analysis

This vulnerability falls under CWE-288 (Authentication Bypass Using an Alternate Path or Channel) and CWE-306 (Missing Authentication for Critical Function). The Simple User Registration plugin fails to properly validate authentication requests across all available pathways, creating an alternate channel through which attackers can bypass the standard authentication flow.

The vulnerability enables account takeover attacks by exploiting flaws in how the plugin handles user authentication and session management. When an attacker identifies and leverages this alternate authentication path, they can assume the identity of any registered user without knowledge of their credentials.

Root Cause

The root cause of CVE-2024-49604 stems from the plugin's failure to enforce consistent authentication checks across all entry points and functions that handle user identity verification. The plugin lacks proper authentication validation for critical functions, allowing requests to reach sensitive operations without appropriate credential verification. This architectural flaw creates a pathway where authentication controls can be entirely circumvented.

Attack Vector

The attack is network-based and requires no prior authentication or user interaction, making it highly exploitable. An attacker can remotely target any WordPress installation running the vulnerable plugin version. The exploitation flow involves:

1. Identifying a WordPress site using Simple User Registration plugin version 5.5 or earlier
2. Crafting malicious requests that leverage the alternate authentication pathway
3. Bypassing standard login mechanisms to gain unauthorized access to target user accounts
4. Achieving full account takeover with the victim's privileges

The network-accessible nature of this vulnerability combined with no authentication requirements creates a significant attack surface for WordPress installations using this plugin. Technical details regarding the specific exploitation mechanism can be found in the Patchstack Advisory on WP Plugin Vulnerability.

Detection Methods for CVE-2024-49604

Indicators of Compromise

• Unusual authentication events or login activity for user accounts without corresponding valid login attempts
• Unexpected session creation or user activity from unfamiliar IP addresses or geolocations
• Anomalous account modifications, password changes, or profile updates not initiated by legitimate users
• Evidence of unauthorized access to user data or administrative functions

Detection Strategies

• Monitor WordPress authentication logs for login events that bypass standard authentication flows
• Implement web application firewall (WAF) rules to detect and block anomalous requests to the Simple User Registration plugin endpoints
• Deploy endpoint detection solutions to identify suspicious patterns associated with authentication bypass attempts
• Audit user session creation events for anomalies indicating unauthorized access

Monitoring Recommendations

• Enable comprehensive logging for all authentication-related events on WordPress installations
• Configure real-time alerting for account modifications or privilege changes
• Implement user behavior analytics to detect account takeover patterns
• Regularly review access logs for signs of exploitation targeting the vulnerable plugin

How to Mitigate CVE-2024-49604

Immediate Actions Required

• Immediately disable or remove the Simple User Registration plugin if running version 5.5 or earlier
• Audit all user accounts for signs of unauthorized access or modification
• Force password resets for all user accounts that may have been compromised
• Review and revoke any suspicious sessions or authentication tokens

Patch Information

At the time of CVE publication, no official patch information was available in the NVD database. Administrators should check the WordPress plugin repository and the Patchstack Advisory for updated version information. Until a patched version is confirmed, consider using alternative user registration solutions for WordPress.

Workarounds

• Disable the Simple User Registration plugin entirely until a security patch is available
• Implement additional authentication layers such as two-factor authentication (2FA) for all user accounts
• Deploy a web application firewall with rules to restrict access to plugin-specific endpoints
• Limit user registration functionality to authenticated administrators only

# WordPress CLI commands to disable the vulnerable plugin
wp plugin deactivate simple-user-registration --path=/var/www/html

# Verify plugin status
wp plugin list --path=/var/www/html | grep simple-user-registration

# Force all users to re-authenticate by invalidating sessions
wp user session destroy --all --path=/var/www/html