CVE-2023-4101
📋 TL;DR
This vulnerability in QSige login SSO allows authenticated users to access resources without proper permission checks. Attackers who have valid login credentials can potentially access sensitive data or functions they shouldn't have permission to view. This affects organizations using vulnerable versions of QSige IDM Sistemas software.
💻 Affected Systems
- QSige IDM Sistemas
📦 What is this software?
Qsige by Qsige
⚠️ Risk & Real-World Impact
Worst Case
Privileged escalation leading to complete system compromise, data exfiltration, or unauthorized administrative actions across the entire QSige environment.
Likely Case
Unauthorized access to sensitive business data, user information, or restricted application functions by authenticated users exceeding their intended permissions.
If Mitigated
Minimal impact with proper access controls and monitoring, though the vulnerability still presents a security weakness that should be addressed.
🎯 Exploit Status
Exploitation requires valid credentials but then bypasses permission checks; relatively straightforward for authenticated attackers
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Not specified in provided references
Vendor Advisory: https://www.incibe.es/en/incibe-cert/notices/aviso/multiple-vulnerabilities-idm-sistemas-qsige
Restart Required: Yes
Instructions:
1. Contact QSige vendor for specific patch information
2. Apply recommended security updates
3. Restart affected services
4. Verify access controls are functioning properly
🔧 Temporary Workarounds
Implement additional access control layer
allAdd application-level permission checks independent of SSO
Restrict user permissions
allApply principle of least privilege to all user accounts
🧯 If You Can't Patch
- Implement network segmentation to isolate QSige systems
- Enable detailed logging and monitoring for unauthorized access attempts
- Implement multi-factor authentication to reduce credential compromise risk
- Regularly audit user permissions and access patterns
🔍 How to Verify
Check if Vulnerable:
Test authenticated access to resources beyond user permissions; check if SSO properly validates authorizationCheck Version:
Check QSige application version through admin interface or configuration filesVerify Fix Applied:
Verify that authenticated users cannot access resources beyond their assigned permissions after patch📡 Detection & Monitoring
Log Indicators:
- Unusual access patterns to sensitive resources
- Multiple failed permission checks followed by successful access
- Access to resources outside normal user behavior patterns
Network Indicators:
- Unusual API calls to sensitive endpoints
- Requests for resources typically restricted to specific user roles
SIEM Query:
source="qsige" AND (event_type="access_denied" OR resource="sensitive_*" OR user_role!="admin" AND action="admin_*")