Ransom:Win32/Ryuk is a deadly computer virus that can leave affected files inaccessible. This virus uses complex algorithmic pattern to lock the files. Most variants of Ransom:Win32/Ryuk also executes data renaming by appending various strings on file extensions. The primary objective of Ransom:Win32/Ryuk virus is to hostage important computer files and takes advantage of the circumstances to extort money from victims.

Threat Behavior

Ransom:Win32/Ryuk spreads globally through various ransomware campaign usually initiated via human-operated modules. Most infection instances are observed to be leveraging from phishing email campaign where Ransom:Win32/Ryuk is deployed as an attachment to messages. It attacks enterprise networks by pretending as valid business correspondence engaging the subject of product inquiry, payment terms, banking details, shipping information, tax, salary, and so on.

Other ways to spread Ransom:Win32/Ryuk may exploit vulnerable services and software. A campaign that focuses on this attack includes web injections, drive-by-downloads, pirated software, and bogus software update.

Once running on the computer and its network, Ransom:Win32/Ryuk steals credentials including username, passwords, IP address, and other useful network and ISP information. Then, it infects other devices to obtain the same details. After scouting and stealing data from computers, Ransom:Win32/Ryuk installs the ransomware module and start targeting important files.


Ransom:Win32/Ryuk can perform different malicious actions once it penetrated the computer. It can download additional files from a remote server to enhance its presence and continuously sends status about the infected system or network. Even though there are so many processes involve in the Ransom:Win32/Ryuk infection, the primary goal of this virus is to extort money from victims. As such, its task is to encrypt targeted files from the infected computer and holds them as hostage. Ransom:Win32/Ryuk asks ransom money from victims as compensation for decryption tool and key that are needed to restore all files back to their original format.

List of Variants

List of Ransom:Win32/Ryuk Variants
Version NameAlert LevelDate Added
Ransom:Win64/RyukSevereOct 10, 2018
Ransom:Win64/Ryuk.ASevereOct 30, 2018
Ransom:Win32/Ryuk.S!MTBSevereDec 31, 2018
Ransom:Win64/Ryuk.PA!MTBSevereApr 03, 2019
Ransom:Win32/Ryuk.P!MTBSevereApr 04, 2019
Ransom:Win32/Ryuk.BSevereJul 30, 2019
Ransom:Win32/Ryuk!MSRSevereOct 04, 2019
Ransom:Win32/Ryuk.AASevereOct 24, 2019
Ransom:Win32/Ryuk.SA!MSRSevereDec 12, 2019
Ransom:Win64/Ryuk.PA!rfnSevereDec 14, 2019
Ransom:Win32/Ryuk.CA!lnkSevereDec 18, 2019
Ransom:Win32/Ryuk.SB!MSRSevereJan 13, 2020
Ransom:Win32/Ryuk.BS!MTBSevereFeb 02, 2020
Ransom:Win64/Ryuk.PB!MTBSevereFeb 11, 2020
Ransom:Win64/Ryuk.PC!MTBSevereFeb 11, 2020
Ransom:Win32/Ryuk.DHA!MTBSevereFeb 25, 2020
Ransom:Win64/Ryuk.PB!rfnSevereFeb 27, 2020
Ransom:Win32/Ryuk.AA!MTBSevereMar 10, 2020
Ransom:Win64/Ryuk.PC!rfnSevereMay 16, 2020
Ransom:Win32/Ryuk.AS!MTBSevereMar 18, 2020
Ransom:Win64/Ryuk.A!MSRSevereMar 20, 2020
Ransom:Win64/Ryuk.B!MSRSevereMar 20, 2020
Ransom:Win64/Ryuk.E!MSRSevereMar 20, 2020
Ransom:Win32/Ryuk.AS!rfnSevereMar 23, 2020
Ransom:Win64/Ryuk.PM!MTBSevereMar 24, 2020
Ransom:Win32/Ryuk.DHA!rfnSevereMar 27, 2020
Ransom:Win64/Ryuk.PD!MTBSevereApr 08, 2020
Trojan:Win32/Ryuk!MTBSevereMay 06, 2020
Ransom:Win32/Ryuk.C!rfnSevereMay 16, 2020
Ransom:Win32/Ryuk.DA!MTBSevereAug 12, 2020
Ransom:Win32/Ryuk!mlSevereAug 14, 2020
Ransom:Win32/Ryuk.ZB!MTBSevereSep 06, 2020
Ransom:Win32/Ryuk.MZ!MTBSevereSep 10, 2020
Ransom:Win32/Ryuk.BY!MTBSevereSep 21, 2020
Ransom:Win32/Ryuk.G!MSRSevereSep 29, 2020
Ransom:Win32/Ryuk.DSC!MTBSevereOct 05, 2020
Ransom:Win32/Ryuk.FSevereNov 03, 2020
Ransom:Win32/Ryuk!MTBSevereNov 03, 2020
Ransom:Win32/Ryuk.DB!MTBSevereNov 03, 2020
For complete details including full list of Ransom:Win32/Ryuk variants, please refer to this Microsoft Security Intelligence page

How to remove Ransom:Win32/Ryuk?

To totally remove Ransom:Win32/Ryuk from the computer and get rid of relevant virus and trojan, please execute the procedures as stated on this page. Make sure that you have completely scan the system with suggested malware removal tools and virus scanners.

Remove Ransom:Win32/Ryuk Instantly

To instantly remove Ransom:Win32/Ryuk, we suggest that you scan the infected computer with this powerful anti-malware tool. It can detect and get rid of Trojans, viruses, malware, and adware from the infected computer. To fully protect the computer against Ransom:Win32/Ryuk or similar attack, you can activate Malwarebytes to have real-time scanning and complete defense against all forms of threats.

1. Download Malwarebytes Anti-Malware from the link below. Save the file on your hard drive.

2. Once the download completes, double-click on the file MBSetup.exe to run the program.

3. Select desired installation package whether for Personal Computer or Work Computer.

4. On next window, click Install button to proceed.

MBAM Default Install

5. Just proceed with the succeeding prompts until it start to execute the installation procedure.

6. Installation process will take less than a minute. It should run automatically after completing the setup.

7. When Malwarebytes Anti-Malware interface appears, please select Scan on the menu. The program will check for any available update before proceeding. Do not skip this step. Virus scan may take a while, please wait for the process to finish.


8. When scanning is done, Malwarebytes Anti-Malware will display the list of identified threats. Remove all and restart the computer to finalized the scan process.

After executing the above instructions, Ransom:Win32/Ryuk should have been eliminated totally from the computer. If there are still signs of infection or computer is displaying unusual behaviors, please continue with the remaining procedures.

Stage 1 : Start Windows in Safe Mode With Networking

Windows 10 Guide

1. Click on Windows logo and select Power icon when options pop-ups.
2. Select Restart from the options while pressing Shift key on the keyboard.
3. Choose an Option window will appear, select the Troubleshoot button.
4. On next window, please choose Advanced Option.
5. On Advanced Option window, click on Startup Settings and then, click Restart button to reboot the computer.
6. When Windows boot on Startup Settings, press function key F5 or number 5 on keyboard.

A simpler alternative for Windows 10 users is to scan the computer with Microsoft Defender Offline. This will run a virus scan in the recovery environment.

Windows 8 Guide

1. Click Windows Start icon at the lower left section of the screen.
2. Open Search window and type Advanced in the field. It will open General PC Settings.
3. Click on Advanced Startup and then, click on Restart Now button.
4. Once the computer starts in Advanced Startup option menu, select Troubleshoot.
5. Next, click on Advanced Options to reveal the next section.
6. Click Startup settings and then, click Restart button to boot the PC in Startup Settings.
7. Use function key F5 or number key 5 to Enable Safe Mode with Networking.

Stage 2 :Double Check with Microsoft Security Apps

Microsoft Windows has built-in security application that you can use to double-check if computer is still infected with Ransom:Win32/Ryuk. For Windows 8 and 10 users, please run Windows Defender. Users of Windows Vista and older versions can utilize Microsoft Security Essentials to remove Ransom:Win32/Ryuk virus.

Windows 8 / 10 Instructions:

Windows Defender is a free tool that was built help you remove Ransom:Win32/Ryuk, viruses, and other malicious items from Windows 8 or Windows 10 system. Follow these procedures to scan your computer with Windows Defender:

1. Tap or click the Search charm, search for defender, and then open Windows Defender.

If Windows Defender is not yet installed on the computer, please proceed to download page using the link below. It also contains detailed instruction to install and use the program effectively. Proper usage is required to totally remove Ransom:Win32/Ryuk


2. On the Home tab, click Full under Scan Options. Click Scan now to start scanning for presence of Ransom:Win32/Ryuk. The process may take a while to complete.


3. After the scan, delete/quarantine identified threats wether it is relevant to Ransom:Win32/Ryuk or not. You may now restart Windows to complete the virus removal process.

Windows XP, Windows Vista, and Windows 7 Instructions:

1. Open Microsoft Security Essentials by going to Windows Start > All Programs. If the tool is not yet installed on the computer, please download Microsoft Security Essentials from the link below. Save the file on your hard drive.

Complete installation guide and usage are also provided on the same link. It is essential in removing Ransom:Win32/Ryuk effectively. If Microsoft Security Essentials is already installed on the PC, please proceed with the steps below.

2. On Microsoft Security Essentials Home screen, please choose Full under Scan Options.

MSE Full Scan

3. Click on Scan Now button to start detecting Ransom:Win32/Ryuk items, viruses, and malware on the PC. Scan may take a while, please be patient and wait for the process to end.

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