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Nmap
I found several ports open like 21, 22 & 1337.

Port 21 (FTP)
Access as anonymous, I found 3 images like below:

So let’s use mget * to get all of the images.
Images
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Since I have play CTF several times. This is called Flag Semaphore and one of the best platforms to decode it using https://www.dcode.fr/semaphore-flag

By decoding the above picture I got “semaphore”

By decoding the above picture I got “signalperson”

Since I got the username & password let’s get the hash & token
HASH = sha256(semaphore + signalperson)
TOKEN = bytesToHex(HASH)I make a simple python script to do this :)

Port 1337
Since I have all of the things needed let’s check on port 1337. It asks for a username, password, and token which I already have.

So I can use ls, pwd and nc. Let’s try to get a reverse shell using nc.
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Flagman (User)
I tried to run linpeas and found this

After reading the file I found a possible password for the flagman.

Try to su flagman and we got in!

Admiral (User)
I try to sudo -l and found this.

Let’s try run the python as admiral.
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Also, I should port forward port 5000 by using SSH.
ssh -L LOCALPORT:127.0.0.1:REMOTEPORT flagman@192.168.0.119
ssh -L 5000:127.0.0.1:5000 flagman@192.168.0.119The first thing I did was to go to /console and put the Debugger PIN and I tried to get a reverse shell from it.

Root
First thing first let’s try sudo -l and I found like below:

We can try check on GTFOBINS
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Nice! I manage to root it :)
