---
title: Rootkits
ms.reviewer: 
description: Rootkits may be used by malware authors to hide malicious code on your computer and make malware or potentially unwanted software harder to remove.
keywords: security, malware, rootkit, hide, protection, hiding, WDSI, MMPC, Microsoft Malware Protection Center, rootkits, Sirefef, Rustock, Sinowal, Cutwail, malware, virus
ms.prod: w10
ms.mktglfcycl: secure
ms.sitesec: library
ms.localizationpriority: medium
ms.author: ellevin
author: levinec
manager: dansimp
audience: ITPro
ms.collection: M365-security-compliance  
ms.topic: article
search.appverid: met150
---
# Rootkits

Malware authors use rootkits to hide malware on your device, allowing malware to persist as long as possible. A successful rootkit can potentially remain in place for years if it is undetected. During this time it will steal information and resources.

## How rootkits work

Rootkits intercept and change standard operating system processes. After a rootkit infects a device, you can’t trust any information that device reports about itself.

For example, if you were to ask a device to list all of the programs that are running, the rootkit might stealthily remove any programs it doesn’t want you to know about. Rootkits are all about hiding things. They want to hide both themselves and their malicious activity on a device.

Many modern malware families use rootkits to try and avoid detection and removal, including:

* [Alureon](https://www.microsoft.com/security/portal/threat/encyclopedia/Entry.aspx?Name=Win32%2fAlureon)

* [Cutwail](https://www.microsoft.com/security/portal/threat/encyclopedia/Entry.aspx?Name=Win32%2fCutwail)

* [Datrahere](https://www.microsoft.com/wdsi/threats/malware-encyclopedia-description?Name=Trojan:Win64/Detrahere) (Zacinlo)

* [Rustock](https://www.microsoft.com/security/portal/threat/encyclopedia/entry.aspx?Name=Win32%2fRustock)

* [Sinowal](https://www.microsoft.com/security/portal/threat/encyclopedia/Entry.aspx?Name=Win32%2fSinowal)

* [Sirefef](https://www.microsoft.com/security/portal/threat/encyclopedia/Entry.aspx?Name=Win32%2fSirefef)

## How to protect against rootkits

Like any other type of malware, the best way to avoid rootkits is to prevent it from being installed in the first place.

* Apply the latest updates to operating systems and apps.

* Educate your employees so they can be wary of suspicious websites and emails.

* Back up important files regularly. Use the 3-2-1 rule. Keep three backups of your data, on two different storage types, and at least one backup offsite.

For more general tips, see [prevent malware infection](prevent-malware-infection.md).

### What if I think I have a rootkit on my device?

Microsoft security software includes a number of technologies designed specifically to remove rootkits. If you think you might have a rootkit on your device and your antimalware software isn’t detecting it, you might need an extra tool that lets you boot to a known trusted environment.

[Microsoft Defender Offline](https://support.microsoft.com/help/17466/microsoft-defender-offline-help-protect-my-pc) can be launched from Windows Security Center and has the latest anti-malware updates from Microsoft. It’s designed to be used on devices that aren't working correctly due to a possible malware infection.

[System Guard](https://cloudblogs.microsoft.com/microsoftsecure/2017/10/23/hardening-the-system-and-maintaining-integrity-with-windows-defender-system-guard/) in Windows 10 protects against rootkits and threats that impact system integrity.

### What if I can’t remove a rootkit?

If the problem persists, we strongly recommend reinstalling the operating system and security software. You should then restore your data from a backup.