difficulty: easy

#2025.10.27

First, add the IP to the "/etc/hosts":

sudo nano /etc/hosts

Then run nmap or rustscan.

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Well, it seems every time it runs the scan it returns filtered IP and nothing interesting.

After googling for a while, I found some nmap UDP scans, so I sure tried them.

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Well, would you look at that.

Port 500 is open with isakmp service. I actually don't know what that service is, so again, Google time.

Internet Security Association and Key Management Protocol

It has vulnerability according to the Wikipedia article above.

So I started researching.

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The ikescan reveals the IPsec VPN config right away.

The gateway accepts PSK authentication with 3DES encryption and SHA1 hashing, plus XAUTH (Extended Authentication) for additional user authentication.

-chatGPT