CVE-2025-14727
📋 TL;DR
A vulnerability in NGINX Ingress Controller's nginx.org/rewrite-target annotation validation allows path traversal attacks. This affects Kubernetes clusters using NGINX Ingress Controller with the vulnerable annotation, potentially enabling attackers to access restricted files or directories.
💻 Affected Systems
- NGINX Ingress Controller
📦 What is this software?
⚠️ Risk & Real-World Impact
Worst Case
Full path traversal leading to arbitrary file read, configuration manipulation, or potential remote code execution depending on system permissions and configuration.
Likely Case
Unauthorized access to sensitive files or directories within the container filesystem, potentially exposing secrets, configuration files, or application data.
If Mitigated
Limited impact with proper network segmentation, minimal container permissions, and restricted file system access.
🎯 Exploit Status
Path traversal vulnerabilities typically have low exploitation complexity when the vulnerable endpoint is accessible.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Check F5 advisory K000158176 for specific patched versions
Vendor Advisory: https://my.f5.com/manage/s/article/K000158176
Restart Required: Yes
Instructions:
1. Review F5 advisory K000158176. 2. Identify affected NGINX Ingress Controller version. 3. Upgrade to patched version. 4. Restart NGINX Ingress Controller pods. 5. Verify annotation validation is working.
🔧 Temporary Workarounds
Disable rewrite-target annotation
linuxRemove or disable the nginx.org/rewrite-target annotation from vulnerable ingress configurations
kubectl edit ingress <ingress-name>
Remove or comment out nginx.org/rewrite-target annotation lines
Implement network restrictions
allRestrict access to NGINX Ingress Controller to trusted networks only
Configure network policies or firewall rules to limit ingress traffic
🧯 If You Can't Patch
- Implement strict network segmentation to limit access to NGINX Ingress Controller
- Apply principle of least privilege to container filesystem and runtime permissions
🔍 How to Verify
Check if Vulnerable:
Check if NGINX Ingress Controller is using nginx.org/rewrite-target annotation: kubectl get ingress -o yaml | grep 'nginx.org/rewrite-target'Check Version:
kubectl describe pod <nginx-ingress-pod> | grep ImageVerify Fix Applied:
After patching, test path traversal attempts against endpoints using rewrite-target annotation should be blocked📡 Detection & Monitoring
Log Indicators:
- Unusual path traversal patterns in access logs
- Failed attempts to access restricted paths
- Multiple 400/403 errors for path manipulation attempts
Network Indicators:
- Unusual HTTP requests containing '../' sequences
- Requests attempting to access sensitive paths
SIEM Query:
source="nginx-ingress" AND (uri="*../*" OR uri="*..\\*" OR status_code=400)