# Privilege Escalation with Autorun Registry

{% hint style="info" %}
Note: The **Wow6432Node** registry entry indicates that you are running a 64-bit Windows version. The operating system uses this key to display a separate view of HKEY\_LOCAL\_MACHINE\SOFTWARE for 32-bit applications that run on 64-bit Windows versions.
{% endhint %}

### Runs

**Commonly known** AutoRun registry:

* `HKLM\Software\Microsoft\Windows\CurrentVersion\Run`
* `HKLM\Software\Microsoft\Windows\CurrentVersion\RunOnce`
* `HKLM\Software\Wow6432Node\Microsoft\Windows\CurrentVersion\Run`
* `HKLM\Software\Wow6432Node\Microsoft\Windows\CurrentVersion\RunOnce`
* `HKCU\Software\Microsoft\Windows\CurrentVersion\Run`
* `HKCU\Software\Microsoft\Windows\CurrentVersion\RunOnce`
* `HKCU\Software\Wow6432Node\Microsoft\Windows\CurrentVersion\Run`
* `HKCU\Software\Wow6432Npde\Microsoft\Windows\CurrentVersion\RunOnce`
* `HKLM\Software\Microsoft\Windows NT\CurrentVersion\Terminal Server\Install\Software\Microsoft\Windows\CurrentVersion\Run`
* `HKLM\Software\Microsoft\Windows NT\CurrentVersion\Terminal Server\Install\Software\Microsoft\Windows\CurrentVersion\Runonce`
* `HKLM\Software\Microsoft\Windows NT\CurrentVersion\Terminal Server\Install\Software\Microsoft\Windows\CurrentVersion\RunonceEx`

Run and RunOnce registry keys cause programs to run each time that a user logs on. The data value for a key is a command line no longer than 260 characters.

**Service runs** \(can control automatic startup of services during boot\):

* `HKLM\Software\Microsoft\Windows\CurrentVersion\RunServicesOnce` 
* `HKCU\Software\Microsoft\Windows\CurrentVersion\RunServicesOnce` 
* `HKLM\Software\Microsoft\Windows\CurrentVersion\RunServices` 
* `HKCU\Software\Microsoft\Windows\CurrentVersion\RunServices`
* `HKLM\Software\Wow6432Node\Microsoft\Windows\CurrentVersion\RunServicesOnce` 
* `HKCU\Software\Wow6432Node\Microsoft\Windows\CurrentVersion\RunServicesOnce` 
* `HKLM\Software\Wow6432Node\Microsoft\Windows\CurrentVersion\RunServices` 
* `HKCU\Software\Wow6432Node\Microsoft\Windows\CurrentVersion\RunServices`

**RunOnceEx:**

* `HKEY_LOCAL_MACHINE\Software\Microsoft\Windows\CurrentVersion\RunOnceEx`
* `HKEY_LOCAL_MACHINE\Software\Wow6432Node\Microsoft\Windows\CurrentVersion\RunOnceEx`

It's not created by default on Windows Vista and newer. Registry run key entries can reference programs directly or list them as a dependency. For example, it is possible to load a DLL at logon using a "Depend" key with RunOnceEx: `reg add HKLM\SOFTWARE\Microsoft\Windows\CurrentVersion\RunOnceEx\0001\Depend /v 1 /d "C:\temp\evil[.]dll"`

{% hint style="info" %}
**Exploit 1**: If you can write inside any of the mentioned registry inside **HKLM** you can escalate privileges when a different user logs in.
{% endhint %}

{% hint style="info" %}
**Exploit 2**: If you can overwrite any of the binaries indicated on any of the registry inside **HKLM** you can modify that binary with a backdoor when a different user logs in and escalate privileges.
{% endhint %}

```bash
#CMD
reg query HKLM\Software\Microsoft\Windows\CurrentVersion\Run
reg query HKLM\Software\Microsoft\Windows\CurrentVersion\RunOnce
reg query HKLM\Software\Wow6432Node\Microsoft\Windows\CurrentVersion\Run
reg query HKLM\Software\Wow6432Node\Microsoft\Windows\CurrentVersion\RunOnce
reg query HKCU\Software\Microsoft\Windows\CurrentVersion\Run
reg query HKCU\Software\Microsoft\Windows\CurrentVersion\RunOnce
reg query HKCU\Software\Wow6432Node\Microsoft\Windows\CurrentVersion\Run
reg query HKCU\Software\Wow6432Node\Microsoft\Windows\CurrentVersion\RunOnce
reg query HKLM\Software\Microsoft\Windows NT\CurrentVersion\Terminal Server\Install\Software\Microsoft\Windows\CurrentVersion\Run
reg query HKLM\Software\Microsoft\Windows NT\CurrentVersion\Terminal Server\Install\Software\Microsoft\Windows\CurrentVersion\RunOnce
reg query HKLM\Software\Microsoft\Windows NT\CurrentVersion\Terminal Server\Install\Software\Microsoft\Windows\CurrentVersion\RunE

reg query HKLM\Software\Microsoft\Windows\CurrentVersion\RunServicesOnce
reg query HKCU\Software\Microsoft\Windows\CurrentVersion\RunServicesOnce
reg query HKLM\Software\Microsoft\Windows\CurrentVersion\RunServices
reg query HKCU\Software\Microsoft\Windows\CurrentVersion\RunServices
reg query HKLM\Software\Wow6432Node\Microsoft\Windows\CurrentVersion\RunServicesOnce
reg query HKCU\Software\Wow6432Node\Microsoft\Windows\CurrentVersion\RunServicesOnce
reg query HKLM\Software\Wow6432Node\Microsoft\Windows\CurrentVersion\RunServices
reg query HKCU\Software\Wow5432Node\Microsoft\Windows\CurrentVersion\RunServices

reg query HKLM\Software\Microsoft\Windows\RunOnceEx
reg query HKLM\Software\Wow6432Node\Microsoft\Windows\RunOnceEx
reg query HKCU\Software\Microsoft\Windows\RunOnceEx
reg query HKCU\Software\Wow6432Node\Microsoft\Windows\RunOnceEx

#PowerShell
Get-ItemProperty -Path 'Registry::HKLM\Software\Microsoft\Windows\CurrentVersion\Run'
Get-ItemProperty -Path 'Registry::HKLM\Software\Microsoft\Windows\CurrentVersion\RunOnce'
Get-ItemProperty -Path 'Registry::HKLM\Software\Wow6432Node\Microsoft\Windows\CurrentVersion\Run'
Get-ItemProperty -Path 'Registry::HKLM\Software\Wow6432Node\Microsoft\Windows\CurrentVersion\RunOnce'
Get-ItemProperty -Path 'Registry::HKCU\Software\Microsoft\Windows\CurrentVersion\Run'
Get-ItemProperty -Path 'Registry::HKCU\Software\Microsoft\Windows\CurrentVersion\RunOnce'
Get-ItemProperty -Path 'Registry::HKCU\Software\Wow6432Node\Microsoft\Windows\CurrentVersion\Run'
Get-ItemProperty -Path 'Registry::HKCU\Software\Wow6432Node\Microsoft\Windows\CurrentVersion\RunOnce'
Get-ItemProperty -Path 'Registry::HKLM\Software\Microsoft\Windows NT\CurrentVersion\Terminal Server\Install\Software\Microsoft\Windows\CurrentVersion\Run'
Get-ItemProperty -Path 'Registry::HKLM\Software\Microsoft\Windows NT\CurrentVersion\Terminal Server\Install\Software\Microsoft\Windows\CurrentVersion\RunOnce'
Get-ItemProperty -Path 'Registry::HKLM\Software\Microsoft\Windows NT\CurrentVersion\Terminal Server\Install\Software\Microsoft\Windows\CurrentVersion\RunE'

Get-ItemProperty -Path 'Registry::HKLM\Software\Microsoft\Windows\CurrentVersion\RunServicesOnce'
Get-ItemProperty -Path 'Registry::HKCU\Software\Microsoft\Windows\CurrentVersion\RunServicesOnce'
Get-ItemProperty -Path 'Registry::HKLM\Software\Microsoft\Windows\CurrentVersion\RunServices'
Get-ItemProperty -Path 'Registry::HKCU\Software\Microsoft\Windows\CurrentVersion\RunServices'
Get-ItemProperty -Path 'Registry::HKLM\Software\Wow6432Node\Microsoft\Windows\CurrentVersion\RunServicesOnce'
Get-ItemProperty -Path 'Registry::HKCU\Software\Wow6432Node\Microsoft\Windows\CurrentVersion\RunServicesOnce'
Get-ItemProperty -Path 'Registry::HKLM\Software\Wow6432Node\Microsoft\Windows\CurrentVersion\RunServices'
Get-ItemProperty -Path 'Registry::HKCU\Software\Wow6432Node\Microsoft\Windows\CurrentVersion\RunServices'

Get-ItemProperty -Path 'Registry::HKLM\Software\Microsoft\Windows\RunOnceEx'
Get-ItemProperty -Path 'Registry::HKLM\Software\Wow6432Node\Microsoft\Windows\RunOnceEx'
Get-ItemProperty -Path 'Registry::HKCU\Software\Microsoft\Windows\RunOnceEx'
Get-ItemProperty -Path 'Registry::HKCU\Software\Wow6432Node\Microsoft\Windows\RunOnceEx'
```

### Startup Path

* `HKCU\Software\Microsoft\Windows\CurrentVersion\Explorer\User Shell Folders`
* `HKCU\Software\Microsoft\Windows\CurrentVersion\Explorer\Shell Folders`
* `HKLM\SOFTWARE\Microsoft\Windows\CurrentVersion\Explorer\Shell Folders`
* `HKLM\SOFTWARE\Microsoft\Windows\CurrentVersion\Explorer\User Shell Folders`

Any shortcut created to the location pointed by subkey Startup will launch the service during logon/reboot. Start up location is specified both at Local Machine and Current User.

{% hint style="info" %}
If you can overwrite any \[User\] Shell Folder under **HKLM**, you will e able to point it to a folder controlled by you and place a backdoor that will be executed anytime a user logs in the system escalating privileges.
{% endhint %}

```bash
reg query "HKCU\Software\Microsoft\Windows\CurrentVersion\Explorer\User Shell Folders" /v "Common Startup"
reg query "HKCU\Software\Microsoft\Windows\CurrentVersion\Explorer\Shell Folders" /v "Common Startup"
reg query "HKLM\SOFTWARE\Microsoft\Windows\CurrentVersion\Explorer\Shell Folders" /v "Common Startup"
reg query "HKLM\SOFTWARE\Microsoft\Windows\CurrentVersion\Explorer\User Shell Folders" /v "Common Startup"

Get-ItemProperty -Path 'Registry::HKCU\Software\Microsoft\Windows\CurrentVersion\Explorer\User Shell Folders' -Name "Common Startup"
Get-ItemProperty -Path 'Registry::HKCU\Software\Microsoft\Windows\CurrentVersion\Explorer\Shell Folders' -Name "Common Startup"
Get-ItemProperty -Path 'Registry::HKLM\SOFTWARE\Microsoft\Windows\CurrentVersion\Explorer\Shell Folders' -Name "Common Startup"
Get-ItemProperty -Path 'Registry::HKLM\SOFTWARE\Microsoft\Windows\CurrentVersion\Explorer\User Shell Folders' -Name "Common Startup"
```

### Winlogon Keys

`HKLM\SOFTWARE\Microsoft\Windows NT\CurrentVersion\Winlogon`

Usually, **Userinit** key points to userinit.exe but if this key can be altered, then that exe will also launch by Winlogon.  
**Shell** key should point to explorer.exe.

```bash
reg query "HKLM\SOFTWARE\Microsoft\Windows NT\CurrentVersion\Winlogon" /v "Userinit"
reg query "HKLM\SOFTWARE\Microsoft\Windows NT\CurrentVersion\Winlogon" /v "Shell"
Get-ItemProperty -Path 'Registry::HKLM\SOFTWARE\Microsoft\Windows NT\CurrentVersion\Winlogon' -Name "Userinit"
Get-ItemProperty -Path 'Registry::HKLM\SOFTWARE\Microsoft\Windows NT\CurrentVersion\Winlogon' -Name "Shell"
```

{% hint style="info" %}
If you can overwrite the registry value or the binary you will be able to escalate privileges.
{% endhint %}

### Policy Settings

* `HKLM\Software\Microsoft\Windows\CurrentVersion\Policies\Explorer` 
* `HKCU\Software\Microsoft\Windows\CurrentVersion\Policies\Explorer`

Check **Run** key.

```bash
reg query "HKLM\Software\Microsoft\Windows\CurrentVersion\Policies\Explorer" /v "Run"
reg query "HKCU\Software\Microsoft\Windows\CurrentVersion\Policies\Explorer" /v "Run"
Get-ItemProperty -Path 'Registry::HKLM\Software\Microsoft\Windows\CurrentVersion\Policies\Explorer' -Name "Run"
Get-ItemProperty -Path 'Registry::HKCU\Software\Microsoft\Windows\CurrentVersion\Policies\Explorer' -Name "Run"
```

### AlternateShell

Path: **`HKLM\SYSTEM\CurrentControlSet\Control\SafeBoot`**

Under the registry key `HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\SafeBoot` is the value **AlternateShell**, which by default is set to `cmd.exe` \(the command prompt\). When you press F8 during startup and select "Safe Mode with Command Prompt," the system uses this alternate shell.  
You can, however, create a boot option so that you don't have to press F8, then select "Safe Mode with Command Prompt."

1. Edit the boot.ini \(c:\boot.ini\) file attributes to make the file nonread-only, nonsystem, and nonhidden \(attrib c:\boot.ini -r -s -h\).
2. Open boot.ini.
3. Add a line similar to the following: `multi(0)disk(0)rdisk(0)partition(1)\WINDOWS="Microsoft Windows XP Professional" /fastdetect /SAFEBOOT:MINIMAL(ALTERNATESHELL)`
4. Save the file.
5. Reapply the correct permissions \(attrib c:\boot.ini +r +s +h\).

Info from [here](https://www.itprotoday.com/cloud-computing/how-can-i-add-boot-option-starts-alternate-shell).

{% hint style="info" %}
**Exploit 1:** If you can modify this registry key you can point your backdoor
{% endhint %}

{% hint style="info" %}
**Exploit 2 \(PATH write permissions\)**: If you have write permission on any folder of the system **PATH** before _C:\Windows\system32_ \(or if you can change it\) you can create a cmd.exe file and if someone initiates the machine in Safe Mode your backdoor will be executed.
{% endhint %}

{% hint style="info" %}
**Exploit 3 \(PATH write permissions and boot.ini write permissions\)**: If you can write boot.ini, you can automate the startup in safe mode for the next reboot.
{% endhint %}

```bash
reg query HKLM\SYSTEM\CurrentControlSet\Control\SafeBoot /v AlternateShell
Get-ItemProperty -Path 'Registry::HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\SafeBoot' -Name 'AlternateShell'
```

### Installed Component

* `HKLM\SOFTWARE\Microsoft\Active Setup\Installed Components`
* `HKLM\SOFTWARE\Wow6432Node\Microsoft\Active Setup\Installed Components`
* `HKCU\SOFTWARE\Microsoft\Active Setup\Installed Components`
* `HKCU\SOFTWARE\Wow6432Node\Microsoft\Active Setup\Installed Components`

Active Setup runs before the Desktop appears. Commands started by Active Setup run synchronously, blocking the logon while they are executing. Active Setup is executed before any Run or RunOnce registry entries are evaluated.

Inside those keys you will find more keys and each for those will home some interesting key-values. The most interesting ones are:

* **IsInstalled:**
  * 0: The component’s command will not run.
  * 1: The component’s command will be run once per user. This is the default \(if the IsInstalled value does not exist\).
*  **StubPath**
  * Format: Any valid command line, e.g. “notepad”
  * This is the command that is executed if Active Setup determines this component needs to run during logon.

{% hint style="info" %}
If you could write/overwrite on any Key with _**IsInstalled == "1"**_ the key **StubPath**, you could point it to a backdoor and escalate privileges. Also, if you could overwrite any **binary** pointed by any **StubPath** key you could be able to escalate privileges.
{% endhint %}

```bash
query "HKLM\SOFTWARE\Microsoft\Active Setup\Installed Components" /s /v StubPath
query "HKCU\SOFTWARE\Microsoft\Active Setup\Installed Components" /s /v StubPath
query "HKLM\SOFTWARE\Wow6432Node\Microsoft\Active Setup\Installed Components" /s /v StubPath
query "HKCU\SOFTWARE\Wow6432Node\Microsoft\Active Setup\Installed Components" /s /v StubPath
```

### Browser Helper Objects

* `HKLM\SOFTWARE\Microsoft\Windows\CurrentVersion\Explorer\Browser Helper Objects`
* `HKLM\SOFTWARE\Wow6432Node\Microsoft\Windows\CurrentVersion\Explorer\Browser Helper Objects`

A **Browser Helper Object** \(**BHO**\) is a DLL module designed as a plugin for Microsoft's Internet Explorer web browser to provide added functionality. These modules are executed for each new instance of Internet Explorer and for each new instance of Windows Explorer. However, a BHO can be prevented to be executed by each instance of Explorer setting the key **NoExplorer** to 1.

BHOs are still supported as of Windows 10, through Internet Explorer 11, while BHOs are not supported in the default web browser Microsoft Edge.

```bash
query "HKLM\SOFTWARE\Microsoft\Windows\CurrentVersion\Explorer\Browser Helper Objects" /s
query "HKLM\SOFTWARE\Wow6432Node\Microsoft\Windows\CurrentVersion\Explorer\Browser Helper Objects" /s
```

Note that the registry will contain 1 new registry per each dll and it will be represented by the **CLSID**. You can find the CLSID info in `HKLM\SOFTWARE\Classes\CLSID\{<CLSID>}`

### Internet Explorer Extensions

* `HKLM\Software\Microsoft\Internet Explorer\Extensions`
* `HKLM\Software\Wow6432Node\Microsoft\Internet Explorer\Extensions`

Note that the registry will contain 1 new registry per each dll and it will be represented by the **CLSID**. You can find the CLSID info in `HKLM\SOFTWARE\Classes\CLSID\{<CLSID>}`

### Font Drivers

* `HKLM\SOFTWARE\Microsoft\Windows NT\CurrentVersion\Font Drivers`
* `HKLM\SOFTWARE\WOW6432Node\Microsoft\Windows NT\CurrentVersion\Font Drivers`

```bash
reg query "HKLM\SOFTWARE\Microsoft\Windows NT\CurrentVersion\Font Drivers"
reg query "HKLM\SOFTWARE\Wow6432Node\Microsoft\Windows NT\CurrentVersion\Font Drivers"
Get-ItemProperty -Path 'Registry::HKLM\SOFTWARE\Microsoft\Windows NT\CurrentVersion\Font Drivers'
Get-ItemProperty -Path 'Registry::HKLM\SOFTWARE\Wow6432Node\Microsoft\Windows NT\CurrentVersion\Font Drivers'
```

### Open Command

* `HKLM\SOFTWARE\Classes\htmlfile\shell\open\command`
* `HKLM\SOFTWARE\Wow6432Node\Classes\htmlfile\shell\open\command`

```bash
reg query "HKLM\SOFTWARE\Classes\htmlfile\shell\open\command" /v ""
reg query "HKLM\SOFTWARE\Wow6432Node\Classes\htmlfile\shell\open\command" /v ""
Get-ItemProperty -Path 'Registry::HKLM\SOFTWARE\Classes\htmlfile\shell\open\command' -Name ""
Get-ItemProperty -Path 'Registry::HKLM\SOFTWARE\Wow6432Node\Classes\htmlfile\shell\open\command' -Name ""
```

## More

Find more Autoruns like registries in [https://www.microsoftpressstore.com/articles/article.aspx?p=2762082&seqNum=2](https://www.microsoftpressstore.com/articles/article.aspx?p=2762082&seqNum=2)

## References

* [https://resources.infosecinstitute.com/common-malware-persistence-mechanisms/\#gref](https://resources.infosecinstitute.com/common-malware-persistence-mechanisms/#gref)
* [https://attack.mitre.org/techniques/T1547/001/](https://attack.mitre.org/techniques/T1547/001/)
* [https://www.microsoftpressstore.com/articles/article.aspx?p=2762082&seqNum=2](https://www.microsoftpressstore.com/articles/article.aspx?p=2762082&seqNum=2)