CVE-2023-27707
📋 TL;DR
This SQL injection vulnerability in DedeCMS allows remote attackers to execute arbitrary SQL commands through the rank_* parameter in the /dede/group_store.php endpoint. Attackers can potentially read, modify, or delete database content, and in some configurations execute arbitrary code. All DedeCMS v5.7.106 installations with the vulnerable endpoint accessible are affected.
💻 Affected Systems
- DedeCMS
📦 What is this software?
Dedecms by Dedecms
⚠️ Risk & Real-World Impact
Worst Case
Full system compromise through SQL injection leading to remote code execution, complete database exfiltration or destruction, and potential lateral movement within the network.
Likely Case
Database information disclosure, privilege escalation within DedeCMS, and potential backdoor installation through SQL injection.
If Mitigated
Limited impact with proper input validation, parameterized queries, and network segmentation preventing database access.
🎯 Exploit Status
Exploitation requires access to the backend (/dede/) which typically requires authentication. However, if default credentials are unchanged or there are other authentication bypasses, exploitation becomes easier.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: v5.7.107 or later
Vendor Advisory: https://www.dedecms.com/
Restart Required: No
Instructions:
1. Backup your current DedeCMS installation and database. 2. Download the latest version from the official DedeCMS website. 3. Replace the vulnerable file /dede/group_store.php with the patched version. 4. Verify the fix by testing the vulnerable endpoint.
🔧 Temporary Workarounds
Input Validation Filter
allAdd input validation to sanitize the rank_* parameter before processing
Modify /dede/group_store.php to add parameter validation: $rank = intval($_GET['rank_*']);
Access Restriction
allRestrict access to the /dede/ directory using web server configuration
For Apache: add 'Deny from all' to .htaccess in /dede/ directory
For Nginx: add 'deny all;' to location block for /dede/
🧯 If You Can't Patch
- Implement Web Application Firewall (WAF) rules to block SQL injection patterns targeting the rank_* parameter
- Disable or remove the /dede/group_store.php endpoint if not required for functionality
🔍 How to Verify
Check if Vulnerable:
Test the /dede/group_store.php endpoint with SQL injection payloads in the rank_* parameter (e.g., rank_test=1' OR '1'='1)Check Version:
Check the DedeCMS version in the admin panel or look for version information in /data/common.inc.phpVerify Fix Applied:
Attempt the same SQL injection test after patching - should return error or no database manipulation📡 Detection & Monitoring
Log Indicators:
- Unusual SQL queries in database logs from the DedeCMS application
- Multiple failed login attempts followed by access to /dede/group_store.php
- HTTP requests containing SQL keywords (UNION, SELECT, etc.) in rank_* parameters
Network Indicators:
- HTTP POST/GET requests to /dede/group_store.php with suspicious parameter values
- Unusual outbound database connections from the web server
SIEM Query:
source="web_logs" AND uri="/dede/group_store.php" AND (param="rank_*" AND value MATCHES "[';]|UNION|SELECT|INSERT|UPDATE|DELETE")