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The mutual authentication process in SD-WAN ensures secure communication between SD-WAN Validators and Controllers. Below is a detailed breakdown of the steps involved:
Step-by-Step Mutual Authentication Process
📌 Step 1: SD-WAN Validator sends its X.509 certificate (signed by a trusted root CA) to prove its identity.
📌 Step 2: The Validator also sends a file containing serial numbers of authorized WAN Edge devices.
📌 Step 3: The SD-WAN Controller checks the Organization Name in the certificate against its configured value. If they match, the peer is verified.
📌 Step 4: The Controller verifies the root CA signature on the certificate. If valid, it trusts the peer.
📌 Step 5: If Steps 3 & 4 pass, the Controller authenticates the Validator, and a temporary DTLS connection is established.
📌 Step 6: The Controller sends its identity certificate to the Validator for mutual verification.
📌 Step 7: The Validator extracts the serial number from the certificate and checks it against the list of authorized Controllers.
📌 Step 8: The Validator compares the Organization Name in the certificate with its configured value.
📌 Step 9: The Validator verifies the root CA signature on the Controller’s certificate.
📌 Step 10: If all checks pass, mutual authentication is complete, and the DTLS connection becomes permanent.
DTLS & Port Hopping in SD-WAN
🚀 DTLS (Datagram Transport Layer Security) is the preferred protocol (UDP-based). WAN Edge routers first attempt to establish control connections using UDP port 12346.
🔄 Port Hopping Mechanism:
- If the first attempt fails, the port increments by +20:
- 12366
- 12386
- 12406
- 12426
- After exhausting these, it loops back to 12346.
⚙️ TLS (Transport Layer Security) is also supported (TCP-based, stateful).
Multi-Core SD-WAN Controller & Manager
🖥️ SD-WAN Controllers and Managers use multiple CPU cores for efficiency:
– DTLS (UDP): Starts at port 12346
– TLS (TCP): Starts at port 23456
💡 Load Balancing: Connections may shift to other base ports for optimal performance.
You Should Know:
Linux & Windows Commands for SD-WAN Security Testing
1. Checking Certificate Details (OpenSSL)
openssl x509 -in certificate.pem -text -noout # View certificate details openssl verify -CAfile rootCA.pem certificate.pem # Verify CA signature
#### **2. Testing DTLS/TLS Connectivity**
openssl s_client -connect <IP>:12346 -dtls1 # Test DTLS openssl s_client -connect <IP>:23456 -tls1_2 # Test TLS
#### **3. Port Scanning (Nmap)**
nmap -sU -p 12346,12366,12386,12406,12426 <SD-WAN_IP> # Check UDP ports nmap -sT -p 23456 <SD-WAN_IP> # Check TCP ports
#### **4. Windows PowerShell: Check Network Connections**
Test-NetConnection -ComputerName <IP> -Port 12346 # Test DTLS
Get-NetTCPConnection -State Established | Where-Object { $_.RemotePort -eq 23456 } # Check TLS
#### **5. Simulating Port Hopping in Linux**
for port in 12346 12366 12386 12406 12426; do nc -uvz <SD-WAN_IP> $port done
## **What Undercode Say**
Mutual authentication in SD-WAN is critical for preventing unauthorized access. Key takeaways:
– Always verify certificates with OpenSSL before deployment.
– Monitor DTLS/TLS ports to detect unauthorized attempts.
– Use port scanning to ensure proper SD-WAN connectivity.
– Automate checks with scripting (Bash/PowerShell) for continuous security validation.
For enhanced security, consider:
- Firewall rules allowing only SD-WAN-related ports.
- Logging all authentication attempts for forensic analysis.
- Regularly updating root CA certificates to prevent MITM attacks.
## **Expected Output:**
A secure, mutually authenticated SD-WAN connection with proper DTLS/TLS port handling and optimized multi-core processing.
**Relevant URLs (if needed):**
References:
Reported By: Breeze Singh – Hackers Feeds
Extra Hub: Undercode MoN
Basic Verification: Pass ✅
