CVE-2022-23632
📋 TL;DR
Traefik versions before 2.6.1 incorrectly handle TLS configuration when requests use fully qualified domain names (FQDNs) in the Host header, potentially causing the wrong TLS certificate to be used. This affects all Traefik deployments using custom TLS configurations with FQDN routing. Attackers could exploit this to intercept or manipulate encrypted traffic.
💻 Affected Systems
- Traefik
📦 What is this software?
Communications Unified Inventory Management by Oracle
View all CVEs affecting Communications Unified Inventory Management →
Traefik by Traefik
⚠️ Risk & Real-World Impact
Worst Case
Man-in-the-middle attacks where encrypted traffic is decrypted using incorrect certificates, potentially exposing sensitive data or enabling credential theft.
Likely Case
TLS configuration mismatch causing certificate warnings for users or service disruption when expected certificates aren't presented.
If Mitigated
Limited impact with proper network segmentation and monitoring, though TLS misconfigurations could still cause service issues.
🎯 Exploit Status
Exploitation requires ability to send HTTP requests with FQDN Host headers to vulnerable Traefik instances.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: 2.6.1
Vendor Advisory: https://github.com/traefik/traefik/security/advisories/GHSA-hrhx-6h34-j5hc
Restart Required: Yes
Instructions:
1. Backup current configuration. 2. Update Traefik to version 2.6.1 or later. 3. Restart Traefik service. 4. Verify TLS configurations work correctly with FQDN requests.
🔧 Temporary Workarounds
Add FQDN to host rules
allExplicitly add FQDNs to router host rules to ensure correct TLS configuration selection
Modify Traefik router configurations to include FQDNs in host rules
🧯 If You Can't Patch
- Implement network-level TLS inspection and monitoring
- Use WAF or reverse proxy in front of Traefik to validate TLS configurations
🔍 How to Verify
Check if Vulnerable:
Check Traefik version and verify if using custom TLS configurations with FQDN routingCheck Version:
traefik versionVerify Fix Applied:
Test requests with FQDN Host headers verify correct TLS certificates are presented📡 Detection & Monitoring
Log Indicators:
- TLS handshake errors
- Certificate mismatch warnings
- Unexpected TLS configuration changes
Network Indicators:
- Unexpected certificate presentations
- TLS protocol anomalies
SIEM Query:
Search for Traefik logs containing 'TLS' and 'configuration' errors or warnings🔗 References
- https://github.com/traefik/traefik/pull/8764
- https://github.com/traefik/traefik/releases/tag/v2.6.1
- https://github.com/traefik/traefik/security/advisories/GHSA-hrhx-6h34-j5hc
- https://www.oracle.com/security-alerts/cpujul2022.html
- https://github.com/traefik/traefik/pull/8764
- https://github.com/traefik/traefik/releases/tag/v2.6.1
- https://github.com/traefik/traefik/security/advisories/GHSA-hrhx-6h34-j5hc
- https://www.oracle.com/security-alerts/cpujul2022.html
