CVE-2020-26766
📋 TL;DR
This CSRF vulnerability in PHPGurukul User Registration & Login System allows attackers to trick authenticated users into performing unintended actions like changing passwords or modifying user data. It affects all installations of version 2.1 where the login system page is accessible. Attackers can exploit this without needing to know the victim's credentials.
💻 Affected Systems
- PHPGurukul User Registration & Login and User Management System With Admin Panel
📦 What is this software?
User Registration \& Login And User Management System With Admin Panel by User Registration \& Login And User Management System With Admin Panel Project
View all CVEs affecting User Registration \& Login And User Management System With Admin Panel →
⚠️ Risk & Real-World Impact
Worst Case
Complete account takeover, privilege escalation to admin, or data manipulation across all user accounts in the system.
Likely Case
Unauthorized password changes, user account modifications, or session hijacking leading to data exposure.
If Mitigated
No impact if proper CSRF tokens and same-origin policies are implemented.
🎯 Exploit Status
Exploitation requires the victim to be authenticated. Attackers craft malicious pages that trigger authenticated requests when visited by logged-in users.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Unknown - No official patch identified
Vendor Advisory: No vendor advisory found
Restart Required: No
Instructions:
1. Check for updated versions beyond 2.1 from PHPGurukul. 2. If no patch exists, implement CSRF protection manually by adding anti-CSRF tokens to all forms and validating them server-side. 3. Ensure same-origin policy headers are properly configured.
🔧 Temporary Workarounds
Implement CSRF Token Protection
allAdd unique anti-CSRF tokens to all forms and validate them on form submission
Manual code modification required - add token generation and validation to PHP files
SameSite Cookie Attribute
allSet SameSite=Strict or Lax attributes on session cookies to prevent cross-site requests
session_set_cookie_params(['samesite' => 'Strict']); in PHP configuration
🧯 If You Can't Patch
- Implement web application firewall (WAF) rules to detect and block CSRF patterns
- Restrict access to the login system page to trusted IP addresses only
🔍 How to Verify
Check if Vulnerable:
Check if forms in the login system lack CSRF tokens by inspecting form HTML for hidden token fields and verifying server-side validation.Check Version:
Check PHPGurukul system version in admin panel or configuration filesVerify Fix Applied:
Test that all forms now include unique CSRF tokens that are validated server-side, and that requests without valid tokens are rejected.📡 Detection & Monitoring
Log Indicators:
- Multiple failed form submissions from same IP with missing/reused tokens
- Unusual user account modifications from unexpected referrers
Network Indicators:
- HTTP requests to login endpoints with missing Referer headers or from external domains
- POST requests without CSRF tokens
SIEM Query:
source="web_logs" AND (uri="/login-system/*" OR uri="/admin/*") AND (missing_field="csrf_token" OR referer_domain!=expected_domain)