TryhackMe - Intermediate Nmap Writeup

Target IP: 10.10.129.48

Box IP: 10.10.142.240

Initial Nmap scan

Lately I've been preferring this scan as my default for CTFs because I get a good understanding of the target without investing TOO much time in things like OS detection or going into the high number ports which more often than not end up not yielding results (this isn't to say not to scan those ports, this is just my own preference)

nmap -T4 -sC -sV 10.10.129.48

Interesting findings...

Although this room is just an example exercise for penetration testing, it's not uncommon in the field to find notes like these or, more often than not, default credentials.

Please practice safe credentials

Since the SSH ports are open we can try logging in with the information we found

ssh ubuntu@10.10.129.48

Provide the found password and... we're in!

Now lets poke around. I like to use this command because usually in CTFs the flag isn't in the user's home directory we need to dig, so I want to have an understanding of the contents in the current directory, as we all the one above.

ls -la ; ls -la ../

Nothing in ubuntu's home directory, but I do see a user directory, so lets look into it.

ls -la ../user

Now cat that flag and you'll have your answer

cat ../user/flag.txt

Even though the room is titled Intermediate Nmap, I think this room helps train curiosity muscles.

Penetration Testing, CTFs, Vulnerability Assessments, Risk Assessments... It doesn't matter what kind of task you have, when dealing with Cyber Security you MUST keep an open and curious mind; knowing how to use tools is great, but unless you train to develop a keen eye to spot the anomalies, the target will slip away with ease.

Be wary though! Curiosity is a double edged blade: it can either help you or waste your time going into a useless rabbit hole left there by the target to get you frustrated and give up. Look up Deceptive Technologies to learn about things like honeypots in order to prepare yourself for these sort of situations and learn how to spot things that will actually yield results.