CVE-2021-3242
📋 TL;DR
CVE-2021-3242 is a SQL injection vulnerability in DuxCMS v3.1.3 that allows attackers to execute arbitrary SQL commands via the s/tools/SendTpl/index?keyword= parameter. This affects all users running the vulnerable version of DuxCMS, potentially compromising database integrity and confidentiality.
💻 Affected Systems
- DuxCMS
📦 What is this software?
Duxcms by Duxcms Project
⚠️ Risk & Real-World Impact
Worst Case
Complete database compromise allowing data theft, modification, or deletion, and potential remote code execution if database permissions allow.
Likely Case
Unauthorized data access, extraction of sensitive information like user credentials, and potential privilege escalation.
If Mitigated
Limited impact with proper input validation, parameterized queries, and database user privilege restrictions in place.
🎯 Exploit Status
Exploitation is straightforward via crafted HTTP requests to the vulnerable endpoint.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: v3.1.4 or later
Vendor Advisory: https://github.com/duxphp/DuxCMS3/issues/4
Restart Required: No
Instructions:
1. Backup your DuxCMS installation and database. 2. Download and install DuxCMS v3.1.4 or later from the official repository. 3. Replace the vulnerable files, particularly those in the s/tools/SendTpl/ directory. 4. Test the application functionality.
🔧 Temporary Workarounds
Input Validation Filter
allImplement server-side input validation to sanitize the keyword parameter.
Modify the SendTpl controller to validate and sanitize input before database queries.
Web Application Firewall (WAF) Rule
allBlock requests containing SQL injection patterns targeting the vulnerable endpoint.
Add WAF rule to block requests to /s/tools/SendTpl/index with suspicious SQL keywords in parameters.
🧯 If You Can't Patch
- Restrict access to the vulnerable endpoint using network ACLs or authentication.
- Implement database user privilege restrictions to limit potential damage from SQL injection.
🔍 How to Verify
Check if Vulnerable:
Check if DuxCMS version is 3.1.3 by reviewing the application files or admin panel. Test by sending a crafted request to /s/tools/SendTpl/index?keyword=test' OR '1'='1 and observing database errors or unexpected behavior.Check Version:
Check the version in the DuxCMS admin panel or review the application's configuration files for version information.Verify Fix Applied:
After patching, test the same endpoint with SQL injection payloads; it should return normal responses without errors or data leakage. Verify the application version is 3.1.4 or later.📡 Detection & Monitoring
Log Indicators:
- Unusual SQL errors in application logs
- Multiple requests to /s/tools/SendTpl/index with suspicious parameters containing SQL keywords like UNION, SELECT, OR
Network Indicators:
- HTTP requests to /s/tools/SendTpl/index with parameters containing SQL injection patterns
SIEM Query:
source="web_logs" AND uri_path="/s/tools/SendTpl/index" AND (query_string="*UNION*" OR query_string="*SELECT*" OR query_string="*OR*" OR query_string="*'*'*")