Ever done a quick vulnerability check only to discover that someone found that vulnerability before you did and already had the system compromised?
During the early stages of a vulnerability scan, nmap is your friend just to quickly confirm what you got. In this case, the big surprise was that the firewall responded on port 4444. Anybody else ever dabbled with pentestingmay be familiar with this port: Metasploit uses port 4444 by default for its remote shell. Other then that, it is typically not used by any well known service.
So at this point, with a possible compromised network firewall, there isnt much point in going much further. A quick connect with netcat oddly enough let to an HTTP error. Upon furhter investigation, it tuns out the Sophosfirewalls use port 4444 for https remote administration. Typically, ports like 8000,8080 or 8443are used, but then again, maybe Sophos wanted to hide their port, or just be different.
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