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Author: Collins Okoth
Category: Featured Software

What is Ransomware How it Works and How to Remove it




Ransomware has grabbed the attention of many internet users, governments, and internet companies in recent years. Although Ransomware has been in existence for a long time, its effects have continued to be felt. Ransomware is short for Ransom Malware, a unique malicious computer program that targets the victim's computer files. The Ransomware usually encrypts the victim's specific files or the entire computer files. The main aim of the Ransomware is to lock the affected users out of the entire computer or out of specific vital files. This paralyzes the everyday activities of the computer user.

Ransomware attackers usually charge a fee in exchange for your encrypted files. For instance, a ransomware attack can be launched on a corporate PC network to encrypt all the files used by the employees. The ransomware attackers will provide a straightforward explanation as to how the company may get their files decrypted. Decrypting the files encrypted by Ransomware is usually an uphill task that may not be performed by the average IT department in most organizations.

Ransomware attackers have evolved to target both small, medium, and large size companies and government institutions since they are sensitive information. There are fewer cases of ransomware attacks that target individual computer users. Likewise, fewer ransomware attacks target innocent users. Perhaps because there is little gain for the ransomware attackers who have been known to charge millions of dollars for high-profile attacks on governments and big companies. Usually, these attackers avoid being traced by using creative means to redirect investigators about their location. Similarly, they request payment by bitcoin, which offers an anonymous payment method.

What is Ransomware How it Works and How to Remove it

Examples of Popular Ransomware and How they Work

 Recently, there has been a surge in the number of Ransomware. However, some ransomware attacks do not make it to the mainstream media because the victims may try to downplay the attacks to retain their good reputation on security measures. For instance, banks would not be willing to announce a ransomware attack on their data since it would be bad for their business model. In addition, many people would not want to save money with a bank or financial institution with security problems. One noticeable ransomware that has dominated the industry is Cerber Ransomware. Apocalypse Ransomware, Petya Ransomware, Jigsaw ransomware, TorrentLocker ransomware, and CryptoWall Ransomware.

It is important to note that Ransomware is classified into three major categories: scareware, screen lockers, and encrypting Ransomware. Let's break them down for better understanding.

  • Scareware

Ransomware attackers use different ways to ensure that their malicious programs infect your computer. For instance, scareware is a special type of Ransomware known to exploit social engineering techniques to get the computer operator to do what they want. Pop-up adverts or notifications usually launch scareware. A common way used by scareware is to appear as a virus threat alert to prompt computer users to click and download a new antivirus. By doing this, you end up downloading and installing malicious Ransomware instead.

  • ScreenLockers

Screen lockers are aggressive ransomware programs that usually lock users from their computers altogether. The screen lockers usually display a full-screen message and give the victim no room to operate the computer. In addition, the screen usually displays information on how to pay the ransom and regain access to your computer. WinLock is an excellent example of a Screen Locker.

  • Encrypting Ransomware

Encrypting Ransomware is far much more advanced than scareware and screen lockers. Encrypting malware usually attacks personal files inside the computer. They encrypt the files using advanced algorithms that are almost impossible to reverse unless you use decrypting keys from the ransomware attackers. Ransomware is currently the most common, and ransomware attackers use it to paralyze large companies and organizations. CryptoLocker is an excellent example of encrypting Ransomware.

How does Ransomware Spread?

Ransomware attacks computers via several different means depending on the type of attack and the target victim. However, there are known and established methods that have been identified to be popular. Ransomware typically spreads via these four main ways,

  • Phishing Emails

Email is a fundamental form of communication over the internet and arguably the most popular among businesses, individuals, and organizations. For this reason, attackers love to use emails as a way to spread their malicious programs.

Phishing emails usually come as unsolicited emails, masquerade as a professional email from a reputable company. These emails are usually designed carefully to serve a purpose making them hard to identify. These emails are usually accompanied by an attachment file that harbors the malicious program. The malware does not necessarily have to be in the form of an executable file; some of these files appear as word docs, zip files, or a Javascript file. Once you click on these files, you unknowingly initiate a process that will then download and install the background's malicious code.

What is Ransomware How it Works and How to Remove it

  • Drive-By Downloads

Drive-by downloads are another efficient way that ransom attackers use to spread Ransomware. These are typically unnoticeable downloads that occur in the background while using your computer to surf the internet. The attackers usually take advantage of vulnerabilities on websites, embed malicious scripts that initiate the entire process. The CryptoWall Ransomware is a popular Ransomware that was spread using this method. 

  • Removable media

Ransomware has increased in popularity due to the increase in potential earnings by the perpetrators. In the past, ransomware attackers have used USB devices and other forms of removable media to spread Ransomware.

  • Remote Desktop Protocol

Using the Remote Desktop Protocol is one of the latest strategies for spreading Ransomware effectively. Attackers can control or manipulate computers that are connected to a specific network remotely. RDP is a tool that allows IT professionals to make configurations and updates remotely on all corporate computers. This activity usually exploits port 3386.

Attackers have similarly exploited this port to perform malicious attacks. They can either gain access by brute force. Online tools such as shodan.io allow these attackers to search and find vulnerable computers with port 3386 left open. Chris and LowLevel04 are some popular ransomware that exploited RDP.

An Example Ransomware at Work - CTB_Locker Ransomware

CTB_Locker is popular ransomware with advanced techniques. The Ransomware encrypts parts of a computer file and embeds a seven-character extension to the encrypted file name. CTB_Locker uses both the Advanced Encryption Standard (AES)  algorithm of encryption and the Elliptic-Curve Diffie-Hellman (ECDH) key agreement protocol. The ECDH should not be mistaken as an encryption algorithm; instead, it uses a unique key agreement protocol. The CTB_Locker ransomware utilizes three different levels of encoding in the following order.

Firstly, the CTB_Locker uses the ECDH randomly generated keys to encode the file; it then utilizes the resultant key to encrypt a randomly generated key by AES. The third and last step is to encrypt the computer files using AES as the encryption algorithm.

How to Remove Ransomware from your PC

When you detect a Ransomware infection on your PC, the first thing you need to do is disconnect all other computers and devices on your shared network to curb the spread of the malware. If you can, you should also disconnect any connected hard drives, cloud storage accounts, and flash drives.

The next step is to find out the type of Ransomware you are dealing with. Generally, encryption ransomware is the hardest to remove from your PC, while screen lockers and scareware may be easier to handle. To identify the kind of Ransomware you are dealing with, you can use the Crypto Sheriff, a tool dedicated to fighting ransomware attacks. Upon running a check on this platform, you will identify the type of Ransomware you have and how to fix it if they have a ready solution. 

Most ransomware files auto-delete themselves from the computer. However, if the malware is still present, you can run Avast premium antivirus to detect the malicious programs and delete them. You can also use other reputable antivirus software such as Kaspersky.

Once you have deleted the malware, you will have to recover your encrypted files through a recovery process. This can be done by restoring tour system files from a backup. You can also restore windows 10 to the previous file versions using the File History feature.

However, some ransomware can block antimalware activity on Windows 10 when you are operating on regular mode. In that case, you will have to use the following procedure to delete the malware. 

In this section, we describe a simpler way to try by yourself to remove most malware from your computer. Note that this procedure will remove the malware but will not decrypt your already encrypted files. Below are the procedural steps that you can take to eliminate malware from your computer.

Reboot your Windows 10 computer in Safe Mode. To do this, you click the Windows logo button and the power button. Then press and hold the shift key, select the Restart option and then go to Troubleshoot and then Advanced options. In the "Advanced Options" category, select "Startup Settings" and click restart. This will display several boot options; choose start windows in safe mode.

Once you are in Safe mode, install antivirus software that you will use to scan your system. Next, scan the entire computer with the antimalware program of your choice to locate the ransomware program. After the scan results are displayed on the screen, you can restore the computer to its previous state. This will inevitably delete the malware program from your computer; however, it will not decrypt the files encrypted with the ransomware.

Conclusion 

It is tricky whether you should opt to pay ransom whenever you are faced with a ransomware attack in your organization, small business, or personal computer. Some people argue that accepting to pay ransom promotes the industry and only fuels more attacks in the coming future. Alternatively, refusal to adhere to the perpetrator's rules may lead to the loss of sensitive information that may be destroyed or shared with the general public. Removing Ransomware from your computer is an advanced-level operation that experts can only perform. However, if you are willing to pay for your loss, most attackers usually provide decryption keys once they receive payment. Sadly, not all ransomware attacks guarantee the full recovery of data after the attack.