CVE-2021-24647
📋 TL;DR
This vulnerability in the Registration Forms WordPress plugin allows unauthenticated attackers to log in as any user by knowing their user ID or username. It affects WordPress sites using vulnerable versions of the plugin. The flaw resides in the social login implementation.
💻 Affected Systems
- Registration Forms – User profile, Content Restriction, Spam Protection, Payment Gateways, Invitation Codes WordPress plugin
📦 What is this software?
Pie Register by Genetechsolutions
⚠️ Risk & Real-World Impact
Worst Case
Complete site takeover where attackers gain administrative access, modify content, install malware, steal sensitive data, and compromise the entire WordPress installation.
Likely Case
Attackers gain unauthorized access to user accounts, potentially accessing sensitive user data, posting malicious content, or performing actions as legitimate users.
If Mitigated
With proper access controls and monitoring, impact is limited to unauthorized access attempts that are detected and blocked before successful exploitation.
🎯 Exploit Status
Exploitation requires only knowledge of user ID or username, making it trivial for attackers who can enumerate users.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: 3.1.7.6
Vendor Advisory: https://wpscan.com/vulnerability/40d347b1-b86e-477d-b4c6-da105935ce37
Restart Required: No
Instructions:
1. Log into WordPress admin panel. 2. Navigate to Plugins → Installed Plugins. 3. Find 'Registration Forms' plugin. 4. Click 'Update Now' if available. 5. Alternatively, download version 3.1.7.6+ from WordPress repository and manually update.
🔧 Temporary Workarounds
Disable Social Login Feature
allTemporarily disable the social login functionality in plugin settings until patched.
Disable Plugin
linuxDeactivate the vulnerable plugin completely if social login is not essential.
wp plugin deactivate registration-forms
🧯 If You Can't Patch
- Implement web application firewall (WAF) rules to block authentication bypass attempts
- Enable detailed logging for authentication events and monitor for suspicious login patterns
🔍 How to Verify
Check if Vulnerable:
Check plugin version in WordPress admin under Plugins → Installed Plugins. If version is below 3.1.7.6, you are vulnerable.Check Version:
wp plugin get registration-forms --field=versionVerify Fix Applied:
Confirm plugin version is 3.1.7.6 or higher. Test social login functionality to ensure proper authentication checks.📡 Detection & Monitoring
Log Indicators:
- Multiple failed login attempts followed by successful login with user ID parameter
- Unusual authentication patterns in WordPress logs
- Social login requests with manipulated user parameters
Network Indicators:
- HTTP POST requests to social login endpoints with user ID parameters
- Unusual authentication traffic patterns
SIEM Query:
source="wordpress.log" AND ("social-login" OR "user_id") AND status=200