What Is Rootkit (Types Of Rootkit & Explanation Of Rootkit)

  Category:  MALWARE | 14th February 2023 | Author:  CSI TEAM

A Rootkit Is A Type Of Malware Designed To Gain Unauthorized Access To A Computer System Or Network And Hide Its Presence From Users And Security Systems. Rootkits Are Often Used By Attackers To Gain Administrative Or "root" Privileges On A System, Allowing Them To Control The System And Carry Out Malicious Activities Such As Stealing Data, Modifying System Files, And Installing Other Types Of malware.

Rootkits Are Typically Difficult To Detect And Remove, As They Are Designed To Hide Their Presence From Antivirus And Anti-malware Software And Other Security Systems. They Can Be Installed Through A Variety Of Methods, Including Exploiting Vulnerabilities In Software, Using Social Engineering Techniques To Trick Users Into Installing Them, Or Through Phishing Attacks.

To Protect Against Rootkits, It Is Important To Implement A Layered Approach To Security That Includes Regular Security Updates And Patches, Strong Access Control Mechanisms, Intrusion Detection And Prevention Systems, And The Use Of Antivirus And Anti-malware Software. It Is Also Important To Practice Safe Computing Habits, Such As Being Cautious When Opening Email Attachments Or Clicking On Links And Avoiding Downloading Software From Unknown Or Untrusted Sources.

Features Of Rootkit

Rootkits Have Several Features That Make Them Particularly Effective And Dangerous As A Type Of Malware. Here Are Some Of Their Key Features:

1. Stealth: Rootkits Are Designed To Hide Their Presence From Users And Security Systems, Making Them Difficult To Detect And Remove. They Often Use Advanced Techniques Such As Hooking Into The Operating System And Modifying System Files To Avoid Detection.

2. Persistence: Rootkits Are Designed To Survive System Reboots And Software Updates, Allowing Them To Maintain Their Presence On An Infected System Over An Extended Period Of Time.

3. Privilege Escalation: Rootkits Are Often Used To Gain Elevated Privileges On A System, Such As Administrative Or "root" Access, Which Allows Attackers To Carry Out A Wide Range Of Malicious Activities.

4. Remote Access: Some Rootkits Are Designed To Provide Remote Access To An Infected System, Allowing Attackers To Control The System From A Remote Location And Carry Out Attacks Or Steal Data.

5. Modification Of System Files: Rootkits Can Modify System Files To Alter The Behavior Of The Operating System, Disable Security Software, Or Install Other Types Of Malware.

6. Difficult To Detect And Remove: Rootkits Can Be Very Difficult To Detect And Remove, Even With Advanced Antivirus And Anti-malware Software. This Is Because They Are Designed To Hide Their Presence And Modify The Operating System In Ways That Make Them Difficult To Detect And Remove.

Different Types Of Rootkit

There Are Several Different Types Of Rootkits, Each With Its Own Unique Characteristics And Methods Of Operation. Here Are Some Of The Most Common Types Of Rootkits:

1. User-mode Rootkits: These Rootkits Run In User Mode And Are Designed To Hide Their Presence And Activities From Other Programs And Users On The System. They Can Be Difficult To Detect, But Are Generally Less Powerful Than Kernel-mode Rootkits.

2. Kernel-mode Rootkits: These Rootkits Operate At The Kernel Level Of The Operating System, Giving Them Higher Privileges And Greater Control Over The System. They Are More Difficult To Detect And Remove Than User-mode Rootkits.

3. Bootloader Rootkits: These Rootkits Modify The Boot Loader Of The Operating System, Allowing Them To Start Before The Operating System And Gain Control Of The System. They Are Very Difficult To Detect And Remove, And Can Survive Even A Complete Reinstallation Of The Operating System.

4. Hypervisor Rootkits: These Rootkits Operate At The Hypervisor Level, Which Is A Layer Of Software That Sits Between The Hardware And The Operating System. They Are Very Difficult To Detect And Remove, And Can Provide Attackers With Complete Control Over The System.

5. Firmware Rootkits: These Rootkits Infect The Firmware Of Devices Such As Routers, network Cards, And Hard Drives, Allowing Attackers To Maintain Control Over A Network Or System Even If The Operating System Is Reinstalled.

6. Virtual Rootkits: These Rootkits Operate Within A Virtual Machine, Allowing Attackers To Gain Control Of A System Without Affecting The Underlying Physical Hardware Or Operating System.

Each Type Of Rootkit Has Its Own Unique Characteristics And Methods Of Operation, Making Them Difficult To Detect And Remove. A Layered Approach To Security That Includes Regular Security Updates And Patches, Strong Access Control Mechanisms, Intrusion Detection And Prevention Systems, And The Use Of Antivirus And Anti-malware Software Can Help Protect Against Rootkit Attacks.

History Of Rootkit

The History Of Rootkits Can Be Traced Back To The 1980s, When Hackers And Other Malicious Actors Began Developing Techniques For Gaining Privileged Access To Computer Systems. One Of The Earliest Documented Examples Of A Rootkit Was The Trojan "The Brain," Which Was Created In 1986 By Two Pakistani Brothers To Protect Their Software From Piracy.

In The 1990s And Early 2000s, Rootkits Became Increasingly Sophisticated, With Attackers Developing Techniques For Hiding Their Presence On A System And Evading Detection By Security Software. In 1999, The "NT Rootkit" Was Released, Which Was One Of The First Rootkits To Use Advanced Techniques Such As Direct Kernel Object Manipulation To Hide Its Presence.

In 2005, The Sony BMG Copy Protection Rootkit Scandal Brought Rootkits Into The Public Spotlight. Sony Had Included A Rootkit In Some Of Its Music CDs As Part Of A Copy Protection Mechanism, But The Rootkit Also Made The CDs Vulnerable To Exploitation By Attackers. The Controversy Surrounding The Incident Led To Lawsuits And A Public Backlash Against The Use Of Rootkits By Companies.

Since Then, Rootkits Have Continued To Evolve, With Attackers Using Increasingly Sophisticated Techniques To Evade Detection And Maintain Control Over Infected Systems. Today, Rootkits Are A Major Threat To Computer And Network Security, And Are Commonly Used In Targeted Attacks And Advanced Persistent Threats. As A Result, Detecting And Removing Rootkits Has Become A Critical Component Of Modern Cybersecurity.

First Rootkit Program

The First Known Rootkit Is Believed To Be A Unix-based Program Called "The Sun Devil" That Was Created By A Group Of Hackers Known As The "The 414s" In 1987. The Sun Devil Rootkit Was Designed To Give The Attackers Root Access To The Targeted System, While Hiding Their Activities From System Administrators And Security Software.

The Rootkit Was Discovered By A Computer Security Expert Named Dan Farmer, Who Developed A Tool Called "chkrootkit" To Detect And Remove Rootkits From Unix-based Systems. The Discovery Of The Sun Devil Rootkit Helped To Raise Awareness Of The Risks Posed By Rootkits And Paved The Way For The Development Of Modern Rootkit Detection And Removal Tools.

How Does Rootkit Work?

Rootkits Work By Hiding Their Presence And Activities On A Computer System, Allowing Attackers To Maintain Control Over The System And Evade Detection By Security Software. Here Are Some Of The Key Steps Involved In A Typical Rootkit Attack:

1. Penetration: The Attacker Gains Access To The System By Exploiting A Vulnerability Or Using Social Engineering Techniques To Trick The User Into Downloading A Malicious File Or Clicking On A Link.

2. Privilege Escalation: The Attacker Gains Administrative Or Root-level Privileges, Which Allow Them To Install And Run The Rootkit Software.

3. Installation: The Rootkit Is Installed On The System And Modified To Hide Its Presence And Activities.

4. Concealment: The Rootkit Modifies The Operating System To Hide Its Presence And Activities From Detection By Security Software, Including Antivirus And Anti-malware Software.

5. Persistence: The Rootkit Is Configured To Run Automatically Whenever The System Boots Up, Allowing The Attacker To Maintain Control Over The System Even After A Reboot.

6. Control: The Attacker Can Use The Rootkit To Perform A Variety Of Malicious Activities, Such As Stealing Sensitive Information, Monitoring User Activity, And Launching Further Attacks On Other Systems Or Networks.

Because Rootkits Are Designed To Evade Detection, They Can Be Very Difficult To Detect And Remove. Detecting And Removing A Rootkit Usually Requires Specialized Tools And Expertise, And May Involve Restoring The System To A Previous State Before The Rootkit Was Installed.

How To Protect The Computer System From Rootkit?

Here Are Some Steps You Can Take To Help Protect Your Computer System From Rootkit Infections:

1. Keep Your Operating System And Software Up-to-date: Install The Latest Security Updates And Patches For Your Operating System, Web Browser, And Other Software To Close Known Vulnerabilities That Could Be Exploited By Rootkits.

2. Use Strong Passwords: Choose Complex, Unique Passwords And Use Two-factor Authentication Wherever Possible To Protect Your Accounts From Unauthorized Access.

3. Install And Update Antivirus And Anti-malware Software: Use Reliable Security Software And Keep It Up-to-date To Detect And Remove Rootkits And Other Malicious Programs.

4. Be Cautious With Email Attachments And Downloads: Avoid Opening Email Attachments And Downloading Files From Untrusted Sources, As They May Contain Malicious Code That Can Install Rootkits On Your System.

5. Use A Firewall: A Firewall Can Help To Prevent Unauthorized Access To Your Computer And Block Suspicious Network Traffic That May Be Associated With Rootkits.

6. Use Virtualization: Consider Using Virtualization Technology To Run Untrusted Applications And Services In A Sandboxed Environment, Which Can Limit The Damage That Rootkits Can Do To Your System.

7. Monitor Your System For Suspicious Activity: Keep An Eye Out For Unusual Behavior Or Unexpected System Changes, Which Could Be Signs Of A Rootkit Infection.

By Implementing These And Other Security Best Practices, You Can Help To Reduce The Risk Of Rootkit Infections And Protect Your Computer System From Unauthorized Access And Data Theft.

How To Remove Rootkit From Infected PC?

Removing A Rootkit From An Infected PC Can Be A Complex And Challenging Process, As Rootkits Are Designed To Be Difficult To Detect And Remove. Here Are Some General Steps You Can Take To Remove A Rootkit From An Infected PC:

1. Disconnect The Infected PC From The Internet And Other Networked Devices To Prevent The Rootkit From Spreading Or Communicating With Its Command And Control Servers.

2. Boot The PC In Safe Mode: Reboot Your Computer In Safe Mode To Prevent The Rootkit From Loading.

3. Use Specialized Removal Tools: Use Specialized Rootkit Removal Tools Like Malwarebytes Anti-Rootkit, Sophos Rootkit Removal, Or Norton Power Eraser To Scan Your Computer For Rootkits And Remove Any Infections.

4. Scan With Antivirus And Anti-malware Software: After Removing The Rootkit, Run A Full Scan Of Your System Using Reputable Antivirus And Anti-malware Software To Detect And Remove Any Other Malware That May Have Been Installed Alongside The Rootkit.

5. Check For System Changes: Once The System Has Been Scanned, Check For Any Unusual Changes To Files, System Settings, And Installed Programs That May Have Been Made By The Rootkit. This May Involve Restoring System Backups, Repairing System Files, And Reinstalling Affected Programs.

6. Stay Vigilant: After Removing The Rootkit, It's Important To Remain Vigilant And Take Steps To Prevent Future Infections By Keeping Your System Up-to-date, Using Reliable Security Software, And Practicing Safe Browsing And Downloading Habits.

If You Are Not Comfortable Performing These Steps Yourself, It's Recommended To Seek Professional Help From A Trusted IT Or Cybersecurity Expert To Help You Remove The Rootkit And Repair Any Damage To Your System.