How to remove Knight Ransomware and decrypt .knight_l files

What is Knight Ransomware

Knight Ransomware is a type of malware that encrypts all the data on a computer, including images, text files, audio files, videos, and more. Knight Ransomware is a rebrand of the Cyclops Ransomware-as-a-Service, which switched its name at the end of July 2023. Once the ransomware infects a computer, it appends the .knight_l extension to every encrypted file and leaves a ransom note named How To Restore Your Files.txt in each folder on the computer. The ransom note demands $5,000 to be sent to a Bitcoin address and contains a link to the Knight Tor site. However, every ransom note in this campaign utilizes the same Bitcoin address of 14JJfrWQbud8c8KECHyc9jM6dammyjUb3Z, which would make it impossible for the threat actor to determine which victim paid a ransom. Knight Ransomware uses AES-256 encryption algorithm to encrypt files. This encryption algorithm is considered to be one of the most secure encryption algorithms available. The ransomware also uses RSA public key (2048 bit) to encrypt the random key used for encryption.

Unfortunately, there are no decryption tools available yet for Knight Ransomware. The group behind Knight operates it as Ransomware-as-a-Service, and these threat actors also offer information-stealing malware. Therefore, there is a possibility that these ransomware infections could have a double-extortion element to them. To decrypt files encrypted by Knight Ransomware, the only solution is to recover them from a backup (if one was created beforehand and is stored elsewhere). Paying the ransom is not recommended as it does not guarantee that the attacker will provide the decryption key.

How Knight Ransomware infected your computer

To infect a computer, Knight Ransomware uses spam campaigns that pretend to be TripAdvisor complaints. The spam emails contain a malicious attachment that, when opened, installs the ransomware on the victim’s computer. First campaigns distributed ZIP archive attachments (TripAdvisorComplaint.zip) that contained EXE file (“TripAdvisor Complaint – Possible Suspension.exe”). However, later versions became more sophisticated and implemented attached HTML documents (TripAdvisor-Complaint-[random-sequence].PDF.htm), that imitated the Tripadvisor website in an opened browser. The fake page showed complaint for a restaurant, that the user is requested to review. The Read Complaint button started the download of an Excel XLL file (TripAdvisor_Complaint-Possible-Suspension.xll). In many cases execution is blocked, however, if not, PC gets infected with Knight Ransomware.

1. Download Knight Ransomware Removal Tool
2. Get decryption tool for .knight_l files
3. Recover encrypted files with Stellar Data Recovery Professional
4. Restore encrypted files with Windows Previous Versions
5. Restore files with Shadow Explorer
6. How to protect from threats like Knight Ransomware

Knight Ransomware files:


README.txt
{randomname}.exe


Knight Ransomware registry keys:

no information

How to decrypt and restore .knight_l files

Use automated decryptors

Download Kaspersky RakhniDecryptor

Use following tool from Kaspersky called Rakhni Decryptor, that can decrypt .knight_l files. Download it here:

Download RakhniDecryptor

There is no purpose to pay the ransom because there is no guarantee you will receive the key, but you will put your bank credentials at risk.

Dr.Web Rescue Pack

Famous antivirus vendor Dr. Web provides free decryption service for the owners of its products: Dr.Web Security Space or Dr.Web Enterprise Security Suite. Other users can ask for help in the decryption of .knight_l files by uploading samples to Dr. Web Ransomware Decryption Service. Analyzing files will be performed free of charge and if files are decryptable, all you need to do is purchase a 2-year license of Dr.Web Security Space worth $120 or less. Otherwise, you don’t have to pay.

If you are infected with Knight Ransomware and removed from your computer you can try to decrypt your files. Antivirus vendors and individuals create free decryptors for some crypto-lockers. To attempt to decrypt them manually you can do the following:

Use Stellar Data Recovery Professional to restore .knight_l files

1. Download Stellar Data Recovery Professional.
2. Click Recover Data button.
3. Select type of files you want to restore and click Next button.
4. Choose location where you would like to restore files from and click Scan button.
5. Preview found files, choose ones you will restore and click Recover.

Download Stellar Data Recovery Professional

Using Windows Previous Versions option:

1. Right-click on infected file and choose Properties.
2. Select Previous Versions tab.
3. Choose particular version of the file and click Copy.
4. To restore the selected file and replace the existing one, click on the Restore button.
5. In case there is no items in the list choose alternative method.

Using Shadow Explorer:

1. Download Shadow Explorer program.
2. Run it and you will see screen listing of all the drives and the dates that shadow copy was created.
3. Select the drive and date that you want to restore from.
4. Right-click on a folder name and select Export.
5. In case there are no other dates in the list, choose alternative method.

If you are using Dropbox:

1. Login to the DropBox website and go to the folder that contains encrypted files.
2. Right-click on the encrypted file and select Previous Versions.
3. Select the version of the file you wish to restore and click on the Restore button.

How to protect computer from viruses, like Knight Ransomware , in future

1. Get special anti-ransomware software

Use ZoneAlarm Anti-Ransomware

Famous antivirus brand ZoneAlarm by Check Point released a comprehensive tool, that will help you with active anti-ransomware protection, as an additional shield to your current protection. The tool provides Zero-Day protection against ransomware and allows you to recover files. ZoneAlarm Anti-Ransomware is compatible with all other antiviruses, firewalls, and security software except ZoneAlarm Extreme (already shipped with ZoneAlarm Anti-Ransomware) or Check Point Endpoint products. The killer features of this application are: automatic file recovery, overwrite protection that instantly and automatically recovers any encrypted files, file protection that detects and blocks even unknown encryptors.

Download ZoneAlarm Anti-Ransomware

2. Back up your files

As an additional way to save your files, we recommend online backup. Local storage, such as hard drives, SSDs, flash drives, or remote network storage can be instantly infected by the virus once plugged in or connected to. Knight Ransomware uses some techniques to exploit this. One of the best services and programs for easy automatic online backup is iDrive. It has the most profitable terms and a simple interface. You can read more about iDrive cloud backup and storage here.

3. Do not open spam e-mails and protect your mailbox

Malicious attachments to spam or phishing e-mails are the most popular method of ransomware distribution. Using spam filters and creating anti-spam rules is good practice. One of the world leaders in anti-spam protection is MailWasher Pro. It works with various desktop applications and provides a very high level of anti-spam protection.

Download MailWasher Pro