What is a Rootkit and How to Detect It?

As technology progresses, there is a considerable rise in cyber attacks, of which computer viruses and other malware are genuine threats. Rootkits are perhaps the most threatening, both in terms of the damage they can pose and the complexity of locating and separating them.

So, what exactly is a rootkit? Before we get to the answer to this question, let’s go over the topics we’ll be discussing in this blog:

• What is a rootkit?
• What is the purpose of the Rootkit?
• Rootkit example
• Types of rootkit
• How does rootkit work?
• How to prevent a rootkit infection?
• What signs indicate a rootkit infection?
• How to remove a rootkit infection?
• Conclusion

What is a rootkit?

Rootkits are malicious computer programs that attackers use to infiltrate a machine in order to gain administrator-level privileges without the owner’s knowledge. A rootkit generally provides an attacker with a backdoor into a computer. Thus, allowing them to gain access to the infected computer and change or remove software and components as they see fit.

Rootkit malware is quite challenging to detect and remove, and attackers often use it to spy on targets or launch attacks on their computers. Rootkit malware can contain various malicious tools, such as bots, to launch a DDoS attack or software that can remove or disable security software, such as keystroke loggers.

What is the purpose of the Rootkit? 

An attacker can use a rootkit for n number of reasons. Some of the most common purposes of using a rootkit are:

Removing the file: A rootkit enters a system via a backdoor, and once inside, the rootkit can run software that can steal or delete files automatically.

Caucusing a malware infection: A rootkit can install malicious software such as viruses, trojan horses, worms, ransomware, spyware, adware, and so on to impair the device’s performance.

Stealing sensitive data: A rootkit can automatically install itself and aim to steal sensitive and private information, typically to sell it or pass it on to unauthorized sources.

Changes system configurations: A rootkit can facilitate access by changing system configurations, such as security authorization privileges.

Intercepts personal information: A rootkit frequently employs keyloggers, which record keystrokes without the user’s knowledge. As a result, personal information, such as credit card numbers and online banking information, is stolen.

You can also explore: What Are Keystroke Loggers & How Do They Work?

Rootkit example 

Application rootkit attacks: When users open infected applications, hackers use application rootkits to gain access to their data. Application rootkit attacks can infiltrate a variety of applications, including spreadsheets, word processing, and so on.

Phishing and social engineering attacks: A rootkit can enter computers via phishing emails and social engineering attacks. Rootkits can also use keyloggers to provide hackers with sensitive user information.

Some of the common real-life examples of rootkit attacks are:

• Flame
• NTRootkit
• Machiavelli
• Greek wiretapping, etc.

Types of rootkit 

There are six types of rootkits based on how they afflict, operate, or remain/survive on the victim’s machine:

Kernel mode

This type of rootkit modifies an operating system’s functionality. This rootkit adds its code and data structures to the kernel, which is the operating system’s core.

Bootloader

This rootkit replaces your computer’s legitimate bootloader with a hacked one, affecting the system even before your operating system boots.

Hardware/ Firmware

This type of rootkit gets its name from where it is installed on your computer. This rootkit can infect the computer’s hard drive, router, and other devices. Hackers can use these rootkits to intercept data written to the disc.

Application/ User mode

These rootkits infect your administrative account, thus changing the computer’s security protocols while hiding themselves. When your computer boots, these rootkits automatically launch.

Memory

Memory rootkits install themselves in computer memory or RAM and remain there until the system RAM is cleared, which usually happens after the computer restarts.

Rootkit virtualization

These rootkits function as malware that runs as a hypervisor and controls one or more VMs. Because all VMs connected to the hypervisor seem to operate normally, these rootkits are less likely to be detected.

How does rootkit work? 

Rootkits function via a process known as modification, which entails changing user account permissions and security. Attackers seeking complete control will use modification to gain unrestricted access to cause damage.

This is all done by rootkits, which can hide themselves to avoid detection, giving attackers complete control of a compromised computer. And they are notable for remaining undetected until they provide remote access to and control of the target device or system. Furthermore, because rootkits cannot spread on their own, attackers typically use covert infection methods.

How to prevent a rootkit infection?

Some of the most common ways to prevent a rootkit infection are:

Maintain system updates. Updates include security fixes that address known vulnerabilities. You are less likely to be compromised by a rootkit if your programmes, including operating systems, are up to date.

Make use of anti-malware software. By combining behaviour analysis, powerful firewalls, and machine learning, anti-malware packages provide adequate defence against rootkit installation and deployment. It also protects against a wide variety of threats.

Use anti-phishing software. Top antivirus companies use a vast list of known phishing sites, as well as certificate checking and crawler blocking, to help avoid phishing attacks and block malicious websites. As a result, the rootkit attack is avoided.

Use software that filters internet traffic. These programs inspect your inbound and outbound traffic to ensure that no malicious software is about to infect your computer. As a result, private and personal information is not leaked to suspect recipients.

Download files sent to you by people you don’t know. Also, be cautious when opening attachments. You should not open attachments sent to you by unknown individuals. This could result in the installation of a rootkit on your computer.

Turn on the safe browsing service. Google’s safe browsing service can protect you from malicious websites and downloads.

What signs indicate a rootkit infection?

It is challenging to detect rootkits. There are no commercial products available to find rootkits. But there are always some signs, and some of those are:

• Antimalware stops. An antimalware application that stops running indicates an active rootkit infection.
• Change in settings. Hackers can manipulate your computer’s operating system with rootkits. If your computer behaves strangely, it could result from a rootkit attack by a hacker.
• Intermittent network activity. If a hacker uses a rootkit to send or receive a large amount of traffic from your computer, your internet connection may slow down.
• Performance issues. Sometimes, slow performance also points to the presence of a rootkit infection.
• Computer lockups. Users cannot access their computers if the system is compromised by a rootkit. The computer may also fail to respond to input from a mouse or keyboard.

How to remove a rootkit infection? 

It is difficult to remove a rootkit because it can hide deep within your OS. But, suppose a rootkit infection infects your system; then you can carry out the below-given steps to remove that:

Step 1: Scan with Microsoft Defender. Go to Windows Security > Virus & Threat Protection and select “Quick scan.” You can also perform a full scan for in-depth scanning.

Step 2: As some of the malware is difficult to remove from your device, choose “scan options” and “Microsoft Defender Offline scan” from the same screen as Virus & threat protection. Your computer will restart once the scan is completed.

Step 3: After restarting, check the scan results. If your PC discovered rootkits, it would notify you that the scan successfully removed them.

Step 4: This step needs to be carried out if you have followed the above steps and rootkits still exist. If a rootkit has infected your system deeply, the only way to remove it is to reinstall Windows. 

Step 5: This step needs to be carried out if you have followed the above steps and rootkits still exist. Some rootkits are capable of infecting the BIOS, which will necessitate a repair. If a rootkit remains after a repair, you may need to purchase a new computer.

Conclusion

Rootkits spread like other malware: via email, USB drives, vulnerabilities, and so on. It can also disrupt the working of an organization or a network by compromising the data. Hence, organizations should implement all standard endpoint protection practices to protect their endpoints. It is preferable to follow the preventive measures discussed in the article rather than to be sorry later!!