CVE-2023-49069
📋 TL;DR
This vulnerability allows unauthenticated remote attackers to distinguish between valid and invalid usernames in Mendix applications using basic authentication. It affects Mendix Runtime versions V8, V9, V10, V10.6, and V10.12 when basic authentication is enabled. Attackers can enumerate valid usernames, which is the first step in credential-based attacks.
💻 Affected Systems
- Mendix Runtime
⚠️ Manual Verification Required
This CVE does not have specific version information in our database, so automatic vulnerability detection cannot determine if your system is affected.
Why? The CVE database entry doesn't specify which versions are vulnerable (no version ranges provided by the vendor/NVD).
🔒 Custom verification scripts are available for registered users. Sign up free to download automated test scripts.
- Review the CVE details at NVD
- Check vendor security advisories for your specific version
- Test if the vulnerability is exploitable in your environment
- Consider updating to the latest version as a precaution
⚠️ Risk & Real-World Impact
Worst Case
Attackers enumerate all valid usernames, then perform targeted password attacks leading to account compromise and potential data breach or privilege escalation.
Likely Case
Attackers identify valid usernames for targeted phishing, social engineering, or brute-force attacks against specific accounts.
If Mitigated
With proper monitoring and rate limiting, only limited username enumeration occurs, detected before significant damage.
🎯 Exploit Status
Username enumeration vulnerabilities are commonly exploited using automated tools. No authentication required.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: V8.18.33, V9.24.31, V10.17.0, V10.6.19, V10.12.11
Vendor Advisory: https://cert-portal.siemens.com/productcert/html/ssa-097435.html
Restart Required: Yes
Instructions:
1. Identify your Mendix Runtime version. 2. Upgrade to the patched version for your release line. 3. Restart the Mendix application. 4. Verify the fix by testing username enumeration.
🔧 Temporary Workarounds
Disable Basic Authentication
allSwitch to alternative authentication mechanisms like OAuth, SAML, or Mendix-native authentication.
Modify application authentication settings in Mendix Studio Pro
Implement Rate Limiting
allAdd rate limiting on authentication endpoints to slow down enumeration attempts.
Configure rate limiting in Mendix application settings or via reverse proxy
🧯 If You Can't Patch
- Implement Web Application Firewall (WAF) rules to detect and block username enumeration patterns
- Enable detailed authentication logging and monitor for unusual authentication attempt patterns
🔍 How to Verify
Check if Vulnerable:
Test authentication endpoint with valid and invalid usernames; if response times or error messages differ, vulnerable.Check Version:
Check Mendix application version in runtime settings or via Mendix Management ConsoleVerify Fix Applied:
After patching, repeat username enumeration tests; responses should be identical for valid and invalid usernames.📡 Detection & Monitoring
Log Indicators:
- Multiple failed authentication attempts with different usernames from same source
- Unusual pattern of authentication requests
Network Indicators:
- High volume of authentication requests to /api/ endpoint
- Requests with sequential or dictionary-based usernames
SIEM Query:
source_ip=* AND (url_path="/api/*/authenticate" OR url_path="/api/*/login") AND status_code=401 | stats count by source_ip, username