Definition
A rootkit is a programme or, more often, a collection of software tools that gives a threat actor a remote access to and control over a computer or other system. While there have been legitimate uses for this type of software, such as to provide remote end-user support, most rootkits open a backdoor on victim systems to introduce malicious software, such as viruses, ransomware, key-logger programmes or other types of malware, or to use the system for further network security attacks. Rootkits often attempt to prevent detection of malicious software by endpoint antivirus software.
How is a Rootkit installed in the systems?
Rootkits can be installed in a number of ways, including phishing attacks or social engineeringtactics to trick users into giving the rootkit permission to be installed on the victim system, often giving remote cybercriminals administrator access to the system.
How does a Rootkit work?
A rootkit is a collection of computer software, typically malicious, that is designed to grant an unauthorised user access to a computer or certain programmes. Once a rootkit is installed, it is easy to mask its presence, so an attacker can maintain privileged access while remaining undetected.
How does a Rootkit hide?
Memory rootkits hide in the RAM memory of your computer. Like kernel rootkits, these can reduce the performance of your RAM memory, by occupying the resources with all the malicious processes involved.
What are the possible outcomes of a rootkit attack?
Today, malware authors can easily purchase rootkits on the dark web and use them in their attacks. The list below explores some of the possible consequences of a rootkit attack:
Sensitive data stolen:
Rootkits enable hackers to install additional malicious software that steals sensitive information, like Credit Card numbers, social security numbers and user passwords, without being detected
Malware infection:
Attackers use rootkits to install malware on computers and systems without being detected. Rootkits conceal the malicious software from any existing anti-malware or antivirus, often de-activating security software without the user’s knowledge. As a result of deactivated anti-malware and antivirus software, rootkits enable attackers to execute harmful files on infected computers
File removal:
Rootkits grant access to all operating system files and commands. Attackers using rootkits can easily delete Linux or Windows directories, registry keys and files
Eavesdropping:
Cybercriminals leverage rootkits to exploit unsecured networks and intercept personal user information and communication, such as e-mails and messages exchanged through chat
Remote control:
Hackers use rootkits to remotely access and change system configurations. Then the hackers can change the open TCP ports inside firewalls or change the system startup scripts
What are the types of rootkit attacks?
Attackers can install different rootkit types on any system. Below, you’ll find a review of the most common rootkit attacks.
Application rootkits:
Application rootkits replace legitimate files with infected rootkit files on your computer. These rootkits infect standard programmes like Microsoft Office, Notepad or Paint. Attackers can get access to your computer every time you run those programmes. Antivirus programmes can easily detect them since they both operate on the application layer
Kernel rootkits:
Attackers use these rootkits to change the functionality of an operating system by inserting malicious code into it. This gives them the opportunity to easily steal personal information
Bootloader rootkits:
The bootloader mechanism is responsible for loading the operating system on a computer. These rootkits replace the original bootloader with an infected one. This means that bootloader rootkits are active even before the operating system is fully loaded
How does one prevent a rootkit attack?
Rootkit attacks are dangerous and harmful but they only infect your computer if you have somehow launched a malicious software that carries the rootkit. The tips below outline the basic steps you should follow to prevent rootkit infection.
Scan your systems:
Scanners are software programmes aimed to analyse a system to get rid of active rootkits.
Rootkit scanners are usually effective in detecting and removing application rootkits. However, they are ineffective against kernel, bootloader or firmware attacks. Kernel level scanners can only detect malicious code when the rootkit is inactive. This means that you have to stop all system processes and boot the computer in the safe mode in order to effectively scan the system.
Security experts claim that a single scanner cannot guarantee the complete security of a system due to these limitations. Therefore, many advise using multiple scanners and rootkit removers. To fully protect yourself against rootkits attacks at the boot or firmware level, you need to back up your data, then reinstall the entire system
Avoid phishing attempts:
Phishing is a type of social engineering attack in which hackers use e-mails to deceive users into clicking on a malicious link or downloading an infected attachment.
The fraudulent e-mail can be anything, from Nigerian prince scams asking to reclaim gold to fake messages from Facebook, requesting you to update your login credentials. The infected attachments can be Excel or Word documents, a regular executable programme or an infected image
Update your software:
Many software programmes contain vulnerabilities and bugs that allow cybercriminals to exploit them—especially older, legacy software. Usually, companies release regular updates to fix these bugs and vulnerabilities but not all vulnerabilities are made public. And once a software has reached a certain age, companies stop supporting them with updates.
Ongoing software updates are essential for staying safe and preventing hackers from infecting you with malware. Keep all your programmes and operating system up-to-date and you can avoid rootkit attacks that take advantage of vulnerabilities
Use next-gen antivirus:
Malware authors always try to stay one step ahead of the cybersecurity industry. To counter their progress, you should use antivirus programmes that leverage modern security techniques, like machine learning-based anomaly detection and behavioural heuristics. This type of antivirus can determine the origin of the rootkit based on its behaviour, detect the malware and block it from infecting your system
Monitor network traffic:
Network traffic monitoring techniques analyse network packets in order to identify potentially malicious network traffic. Network analytics can also mitigate threats more quickly, while isolating the network segments that are under attack to prevent the attack from spreading.