What Is a Rootkit Malware: Definition and Protection
Table of Contents
- By Bryan Lee
- Sep 25, 2023
Modern computers and anti-malware programs are incredibly sophisticated. Their power causes users to believe that any threats will be swiftly detected and dealt with. However, malicious actors have also worked hard to make their attacks harder and harder to detect.
One of the best examples of these efforts is rootkit malware. Although rootkits started off as a “white hat” tool for administrators, they have devolved into dangerous programs that threaten your private information and lead to identity theft.
What is Rootkit?
A rootkit is a malware program that takes remote control of a device and steals its data. As its name suggests, a rootkit grants the hacker privileged access (root) to the machine.
This level of access gives a criminal a lot of options. They can launch distributed denial-of-service (DDoS) attacks, install a keylogger to record the user’s account credentials, or directly remove files and programs from a system.
Worst of all, a rootkit is incredibly challenging to detect with traditional security techniques as it actively hides behind other programs. This trait allows rootkits to remain on a machine for long stretches of time.
Rootkit malware can weasel its way onto your machine in many ways. The most preferred and easiest method is through a social engineering attack. This refers to attacks that trick users into downloading a suspicious program by manipulating an emotion like trust, fear, or anxiety.
Many hackers hijack messenger accounts and send infected links to everyone in that account’s contact list. Once the victim clicks the link, their computers become infected and join the botnet. This allows the hacker to access a new contact list and repeat the process.
Other methods of injecting rootkit onto a device include:
Seemingly trustworthy software isn’t always safe. An easy way for hackers to inject rootkits onto a computer is by bundling it up with a less suspicious program. The rootkit automatically installs and runs under the radar. This is piggybacking.
When the user agrees to the download, they agree to ALL of the associated files. There isn’t a second prompt asking about the rootkit.
Similar to piggybacking, a rootkit can also be attached to another malicious program. Once the virus activates, it also loads the rootkit. This means that the rootkit, which was installed separately, will remain even if you remove the virus. This two-prong approach is particularly dangerous as it lulls users into a false sense of security.
Types of Rootkits
Rootkits are generally categorized based on how deeply they penetrate your operating system. All of them are dangerous if left alone for long enough, but the more sophisticated rootkits are multiple times harder to detect and remove.
Hardware rootkits are lower-level malware that aim for a specific piece of hardware. Possible targets include routers, storage drives, and network cards. Many hardware rootkits reinstall whenever you reboot your computer. This means that simply removing the software isn’t effective in the long run.
Kernel Mode Rootkits
Unlike hardware rootkits, kernel-mode rootkits go deeper and latch onto a computer’s operating system. Attacking the OS allows the rootkit to change, add, or replace anything it wants, barring the BIOS.
Despite their significant threat, kernel mode rootkits are reasonably obvious. Operating systems are fragile, and a single change can bring the whole thing crashing down. So, kernel-mode rootkits often lead to crashes or decreased performance, quickly telling the user that something is wrong.
Bootkit is short for “bootloader rootkit.” Bootkits are a variety of kernel-mode rootkits that attach to the Master Boot Record, which tells your machine how to load its operating system. Since the Master Boot Record is consulted on every boot, the bootkit can take over and load concurrently.
Most anti-virus programs focus on scanning within the operating system for threats. This means bootkits, which exist outside the OS, are virtually invisible.
Memory rootkits are the most short-lived rootkit type on this list. They load into the random-access memory (RAM) and disappear when the system restarts. These rootkits aim to reduce the system’s power and performance by overloading the RAM.
Application rootkits replace a computer’s files with rootkit versions. Frequently used applications like Notepad and Calculator are often targeted. That’s because these programs are relatively simple and can run even when the rootkit is draining the system’s resources.
Virtual machines recreate another operating system on your computer. It’s a feature that allows users to access normally unavailable programs from their primary device. However, having multiple operating systems running presents unique dangers.
A virtual OS is typically less protected than your primary OS and loads on a different layer, similar to kernel mode rootkits. This allows virtual rootkits to go undetected by rootkit scanners installed on your primary OS.
How to Detect and Prevent Rootkits
Locating and removing rootkits on your machine is a tall order, but rootkit scanners have come a long way, and running a scan every now and then is worth it.
What is a Rootkit Scanner?
Just like anti-virus, rootkit scanners probe a system for unwanted software. Scanner’s weakness is that they can only operate in the operating system, making them ineffective at detecting sophisticated rootkits booting at the kernel.
Another detection option is analyzing the Window’s memory dump following a crash. This file is difficult to navigate but can reveal signs of a rootkit’s presence.
The best protection is a solid education. Since you’re reading this article, that means you’re already on the right track. Companies should prioritize teaching anyone with server access how to avoid common social engineering attacks. The program should start with phishing before expanding into more niche threats.
Restricting the types of applications allowed on work-related devices is also a prudent measure. However, the advent of remote work and the blurred lines between personal and work devices make this challenging to enforce.
The top habits you can start building today to stay rootkit-free include:
- Download Software from Official Sources Only: Hackers frequently upload tainted versions of trusted applications for others to download. Avoid piggybacking by purchasing directly from the software’s developer.
- Carefully Examine Emails Before Clicking Links: This tip holds true for all internet safety aspects, not just rootkit prevention. Utilize the preview features of your email browser and check to see if a link is legitimate or not. Other ways to pick out a malicious email are by checking the sender’s address for typos or looking at the grammar of the message itself.
- Keep Your Operating System Up-to-Date: Windows 8 introduced the Secure Boot feature, which made bootkits virtually obsolete. Operating systems frequently introduce small patches that address known security flaws and may be the difference between ending up with a rootkit or not.
How to Get Rid of Rootkit?
Rootkit detection is a complicated business. Many behavior and signature-based detection methods look into changing patterns on your devices to confirm rootkits. However, these options aren’t readily available to the casual user.
If the rootkit is deeply embedded, not even a factory reset may be enough to eliminate it. Users looking to ensure their device is rootkit-free must wipe all their hardware and bios, clear the complementary metal-oxide-semiconductor (CMOS), and reinstall the operating system. This process is challenging and is best tackled by a professional.
Rootkits are like the bug that accidentally gets into your house. Letting it in is laughably easy, but it feels impossible to get out. Prevention should be your number one priority, while scanners mainly confirm that you’re still safe. Contact our team at InfoPay to learn more about defending against rootkits and protecting your digital privacy.