CVE-2023-6718
📋 TL;DR
CVE-2023-6718 is an authentication bypass vulnerability in Repox that allows remote attackers to create or modify user accounts without authentication by sending specially crafted POST requests. This affects all Repox deployments with vulnerable versions exposed to network access. The vulnerability stems from missing authentication mechanisms on certain endpoints.
💻 Affected Systems
- Repox
📦 What is this software?
Repox by Europeana
⚠️ Risk & Real-World Impact
Worst Case
Complete compromise of the Repox system with unauthorized user creation, privilege escalation, and potential data manipulation or exfiltration.
Likely Case
Unauthorized users gain administrative access, create backdoor accounts, or modify existing user permissions.
If Mitigated
Limited impact if network access is restricted and proper authentication controls are implemented.
🎯 Exploit Status
Simple HTTP POST request exploitation; no authentication required.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Check vendor advisory for specific patched version
Vendor Advisory: https://www.incibe.es/en/incibe-cert/notices/aviso/multiple-vulnerabilities-repox
Restart Required: Yes
Instructions:
1. Review vendor advisory for patched version. 2. Backup current configuration. 3. Apply vendor-provided patch or upgrade to fixed version. 4. Restart Repox service. 5. Verify authentication is now required for user management endpoints.
🔧 Temporary Workarounds
Network Access Restriction
linuxRestrict network access to Repox administration interfaces
iptables -A INPUT -p tcp --dport [REPOX_PORT] -s [TRUSTED_NETWORK] -j ACCEPT
iptables -A INPUT -p tcp --dport [REPOX_PORT] -j DROP
Web Application Firewall Rules
allBlock unauthorized POST requests to user management endpoints
WAF rule: Block POST requests to /api/users/* from untrusted sources
🧯 If You Can't Patch
- Isolate Repox instance behind firewall with strict access controls
- Implement network monitoring for suspicious POST requests to user endpoints
🔍 How to Verify
Check if Vulnerable:
Test if POST requests to user management endpoints succeed without authenticationCheck Version:
Check Repox version in web interface or configuration filesVerify Fix Applied:
Verify authentication is now required for all user management operations📡 Detection & Monitoring
Log Indicators:
- Unauthenticated POST requests to user creation/modification endpoints
- Unexpected user account creation events
Network Indicators:
- HTTP POST requests to /api/users/* from unauthorized sources
- Unusual authentication bypass patterns
SIEM Query:
source="repox" AND (http_method="POST" AND uri_path="/api/users/*") AND NOT auth_success="true"