CVE-2020-22198
📋 TL;DR
This CVE describes a SQL injection vulnerability in DedeCMS 5.7 that allows attackers to execute arbitrary SQL commands via the mdescription parameter in member/ajax_membergroup.php. This affects all DedeCMS 5.7 installations with the vulnerable component enabled. Attackers can potentially access, modify, or delete database content.
💻 Affected Systems
- DedeCMS
📦 What is this software?
Dedecms by Dedecms
⚠️ Risk & Real-World Impact
Worst Case
Complete database compromise leading to data theft, data destruction, or full system takeover via subsequent attacks.
Likely Case
Unauthorized data access, privilege escalation, or data manipulation within the DedeCMS database.
If Mitigated
Limited impact with proper input validation and parameterized queries preventing SQL injection.
🎯 Exploit Status
Exploitation requires access to the vulnerable endpoint but is technically simple once accessed.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: 5.7 SP2 or later
Vendor Advisory: https://github.com/blindkey/DedeCMSv5/issues/1
Restart Required: No
Instructions:
1. Download the latest DedeCMS version from the official repository. 2. Replace the vulnerable member/ajax_membergroup.php file with the patched version. 3. Verify the fix by testing the mdescription parameter.
🔧 Temporary Workarounds
Input Validation Filter
allAdd input validation to sanitize the mdescription parameter before processing.
Modify member/ajax_membergroup.php to include parameterized queries or input sanitization.
Access Restriction
allRestrict access to the vulnerable endpoint via web server configuration.
Add 'Deny from all' to .htaccess for member/ajax_membergroup.php directory or equivalent in nginx.
🧯 If You Can't Patch
- Implement a Web Application Firewall (WAF) with SQL injection rules.
- Disable or remove the member/ajax_membergroup.php file if not required.
🔍 How to Verify
Check if Vulnerable:
Test the mdescription parameter in member/ajax_membergroup.php with SQL injection payloads like ' OR '1'='1.Check Version:
Check DedeCMS version in the admin panel or via the system information file.Verify Fix Applied:
Verify that SQL injection attempts no longer succeed and that parameterized queries are implemented.📡 Detection & Monitoring
Log Indicators:
- Unusual SQL queries in database logs
- Multiple requests to member/ajax_membergroup.php with suspicious parameters
Network Indicators:
- HTTP requests containing SQL keywords in mdescription parameter
SIEM Query:
source="web_logs" AND uri="/member/ajax_membergroup.php" AND (param="mdescription" AND value CONTAINS "' OR" OR value CONTAINS "UNION" OR value CONTAINS "SELECT")