CVE-2015-6537
📋 TL;DR
This SQL injection vulnerability in Epiphany Cardio Server 3.3 allows remote attackers to execute arbitrary SQL commands through the login page. Attackers can potentially bypass authentication, access sensitive medical data, or take control of the database server. Healthcare organizations using this specific version are affected.
💻 Affected Systems
- Epiphany Cardio Server
📦 What is this software?
Cardio Server by Epiphanyhealthdata
⚠️ Risk & Real-World Impact
Worst Case
Complete database compromise leading to exposure of sensitive patient health information (PHI), authentication bypass allowing administrative access, and potential remote code execution on the database server.
Likely Case
Authentication bypass allowing unauthorized access to patient records and medical data, potentially leading to data theft or manipulation of healthcare information.
If Mitigated
Limited impact with proper input validation, parameterized queries, and network segmentation preventing external access to the vulnerable login page.
🎯 Exploit Status
SQL injection via login page typically requires minimal technical skill. The vulnerability is in a healthcare system, making it an attractive target for attackers.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Version 3.3.1 or later
Vendor Advisory: http://www.epiphanyhealthdata.com/blog/certresponse
Restart Required: Yes
Instructions:
1. Download the patch from Epiphany Health Data. 2. Backup the current installation and database. 3. Apply the patch following vendor instructions. 4. Restart the Cardio Server service. 5. Verify the fix by testing the login page with SQL injection attempts.
🔧 Temporary Workarounds
Network Segmentation
allRestrict access to the Cardio Server login page to only authorized internal networks using firewall rules.
Web Application Firewall
allDeploy a WAF with SQL injection protection rules in front of the Cardio Server.
🧯 If You Can't Patch
- Implement strict input validation and parameterized queries in the login page code if source access is available.
- Monitor authentication logs for suspicious login attempts and implement account lockout policies.
🔍 How to Verify
Check if Vulnerable:
Test the login page with SQL injection payloads like ' OR '1'='1 in username/password fields. If authentication bypass occurs, the system is vulnerable.Check Version:
Check the Cardio Server administration interface or installation directory for version information (typically shows in web interface footer or about page).Verify Fix Applied:
After patching, attempt the same SQL injection tests. Authentication should fail properly without database errors appearing.📡 Detection & Monitoring
Log Indicators:
- Unusual SQL error messages in application logs
- Multiple failed login attempts with SQL-like patterns
- Successful logins from unexpected IP addresses
Network Indicators:
- HTTP requests to login page containing SQL keywords (SELECT, UNION, etc.)
- Unusual database connection patterns from the application server
SIEM Query:
source="cardio_server_logs" AND (message="*sql*" OR message="*syntax*" OR message="*union*" OR message="*select*")