CVE-2020-6140
📋 TL;DR
This SQL injection vulnerability in OS4Ed openSIS 7.3 allows attackers to execute arbitrary SQL commands through the password reset functionality. Attackers can potentially access, modify, or delete database contents. All openSIS 7.3 installations with the vulnerable ResetUserInfo.php page are affected.
💻 Affected Systems
- OS4Ed openSIS
📦 What is this software?
Opensis by Os4ed
⚠️ Risk & Real-World Impact
Worst Case
Complete database compromise leading to data theft, privilege escalation, authentication bypass, and potential remote code execution if database functions allow it.
Likely Case
Unauthorized access to sensitive student/staff data, password hash extraction, and potential system takeover through admin account compromise.
If Mitigated
Limited impact with proper input validation, parameterized queries, and database permission restrictions in place.
🎯 Exploit Status
SQL injection via password_stf_email parameter requires no authentication and has public proof-of-concept available.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: openSIS 7.4 or later
Vendor Advisory: https://www.os4ed.com/
Restart Required: No
Instructions:
1. Upgrade to openSIS 7.4 or later. 2. Apply vendor-provided patches if available for 7.3. 3. Replace ResetUserInfo.php with patched version.
🔧 Temporary Workarounds
Input Validation Filter
allAdd server-side validation to reject malicious input in password_stf_email parameter
Modify /opensis/ResetUserInfo.php to validate email format and sanitize input
WAF Rule
allImplement web application firewall rules to block SQL injection patterns
Add WAF rule: Detect and block SQL keywords in password_stf_email parameter
🧯 If You Can't Patch
- Disable the password reset functionality temporarily
- Implement network-level restrictions to limit access to /opensis/ResetUserInfo.php
🔍 How to Verify
Check if Vulnerable:
Test the password reset page with SQL injection payloads in password_stf_email parameterCheck Version:
Check openSIS version in admin panel or configuration filesVerify Fix Applied:
Verify that SQL injection attempts no longer succeed and input is properly sanitized📡 Detection & Monitoring
Log Indicators:
- Unusual SQL errors in application logs
- Multiple failed password reset attempts with SQL patterns
- Access to ResetUserInfo.php with suspicious parameters
Network Indicators:
- HTTP POST requests to /opensis/ResetUserInfo.php containing SQL keywords
- Unusual database query patterns from web server
SIEM Query:
source="web_logs" AND uri="/opensis/ResetUserInfo.php" AND (password_stf_email CONTAINS "UNION" OR password_stf_email CONTAINS "SELECT" OR password_stf_email CONTAINS "--")