CVE-2025-54468
📋 TL;DR
Rancher Manager's /meta/proxy endpoint improperly forwards Impersonate-Extra-* headers to external entities like amazonaws.com, potentially leaking sensitive user information such as email addresses. This affects all Rancher Manager deployments using the vulnerable endpoint for external API calls. The vulnerability exposes identifiable data that could be used for reconnaissance or targeted attacks.
💻 Affected Systems
- Rancher Manager
⚠️ 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 intercept sensitive user information (email addresses, authentication details) from Impersonate-Extra headers, enabling targeted phishing, credential harvesting, or identity-based attacks against Rancher users.
Likely Case
Information disclosure of user email addresses and potentially other identifiable metadata to external services, violating privacy expectations and potentially enabling reconnaissance.
If Mitigated
Limited impact with proper network segmentation and external service trust relationships, though information leakage still occurs.
🎯 Exploit Status
Exploitation requires ability to intercept or access traffic between Rancher and external services, or compromise the external service receiving the headers.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Check Rancher security advisory for specific patched versions
Vendor Advisory: https://github.com/rancher/rancher/security/advisories/GHSA-mjcp-rj3c-36fr
Restart Required: Yes
Instructions:
1. Review Rancher security advisory GHSA-mjcp-rj3c-36fr. 2. Upgrade Rancher Manager to patched version. 3. Restart Rancher services after upgrade. 4. Verify headers are no longer forwarded.
🔧 Temporary Workarounds
Network Segmentation
allRestrict Rancher /meta/proxy endpoint access to trusted external services only
Configure network firewalls to limit outbound connections from Rancher to necessary external APIs only
Header Filtering Proxy
linuxDeploy a reverse proxy that strips Impersonate-Extra-* headers before forwarding to external services
nginx config: proxy_set_header Impersonate-Extra-* "";
Apache config: RequestHeader unset Impersonate-Extra-*
🧯 If You Can't Patch
- Implement network monitoring to detect Impersonate-Extra-* headers in outbound traffic
- Audit and minimize external service integrations using /meta/proxy endpoint
🔍 How to Verify
Check if Vulnerable:
Monitor outbound traffic from Rancher to external services for Impersonate-Extra-* headers in HTTP requestsCheck Version:
kubectl get pods -n cattle-system -l app=rancher -o jsonpath='{.items[0].spec.containers[0].image}'Verify Fix Applied:
Confirm Impersonate-Extra-* headers are no longer present in outbound requests to external services after patching📡 Detection & Monitoring
Log Indicators:
- Outbound proxy requests containing Impersonate-Extra-* headers in Rancher logs
- External service logs showing receipt of unexpected authentication headers
Network Indicators:
- HTTP traffic from Rancher to external domains containing Impersonate-Extra-* headers
- Unusual outbound connections to cloud service APIs
SIEM Query:
source="rancher" AND "Impersonate-Extra" AND outbound