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KCTF Locker ransomware. How to remove? (Uninstall guide)

removal by Gabriel E. Hall - - | Type: Ransomware

KCTF Locker ransomware is yet another cyber threat that poses as an educational ransomware

KCTF Locker ransomware virus
KCTF Locker ransomware is a virus developed for educational purposes. At the moment, it is targeting Japanese-speaking users.

KCTF Locker ransomware is a file-encrypting virus that was supposedly invented for educational purposes. However, no educational organization or service is linked to this threat, and the only ones who should be blamed are hackers. The main targets of this ransomware[1] are Japanese-speaking users as the ransom note it displays is written in this language, and the sample of the virus was uploaded from East Asia IP address. KCTF Locker modifies the victim's data by using the XOR encryption method, and, after the process, marks locked files with .DWG file extension. After the encryption, files become useless. The ransom note, which was called as KCTF LOCKER, typically states that files have been encrypted and that the victim needs to pay 10 BTC to the provided wallet to get them restored.

Name KCTF Locker ransomware
Type Cryptovirus
File extension .DWG appendix
Targeted country Japan
Encryption method Xor 
Ransom amount 10BTC
Ransom note Displayed in a program window called KCTF LOCKER
Distribution  Spam email attachments
Elimination Remove KCTF Locker ransomware using your guide below and use Reimage to delete virus damage

KCTF Locker ransomware is a cryptovirus that modifies various data on the infected system. For the encryption, it chooses anything from photos, videos to documents or even archives. The virus typically changes the code of the data by using the predetermined encryption algorithm to make it useless. You can identify encrypted files because ransomware is appending .DWG file extension to the locked data.

After the encryption is done using XOR encryption method, virus generates a ransom note and places it as a program window on the screen. The message called KCTF LOCKER displays the following text:

Your data has been encrypted.
If you want to restore, please pay 10 BTC below

KCTF Locker ransomware demands to 10 BTC for the locked files, but we do not recommend paying this fee or even contacting these cybercriminals in any way. Any communication between the victim and hackers can lead you to the permanent data or money loss. 

You need to remove KCTF Locker ransomware as soon as possible, so you can clean your device and restore locked data. Since the threat can block your antivirus, you should reboot the device in Safe Mode with Networking and then run a scan. You can find alternative removal methods down below as well as the ransomware tends to block its victims and prevent its removal.

After the proper KCTF Locker removal, you need to fix the damage this threat caused. You can use reputable anti-malware like Reimage for the job. This tool scans your system thoroughly and detects various system vulnerabilities and other possible threats. If you are planning to do a data recovery using a backup, you can only do that after the device is fully cleaned. Ransomware can encrypt newly added data too. 

Spam emails have been used to spread direct malware script

Malicious actors have been widely using email campaigns to distribute their viruses. They have been luring people to open safe-looking emails and download file attachments with macro-virus[2] or direct malware script. Typically, these malicious emails look legitimate because virus developers tend to hide their products under well-known company names and logos. 

You should be aware of these techniques and, every time you get an email you are not expecting, delete these messages without opening. If you downloaded the file from the email that was affected by ransomware, the minute you open it malware installs direct script to your device and your system gets infected. 

You can avoid this if you scan every file with an antivirus before opening it on the device. Also, you can look for red flags on these emails. For example, if the email contains various ads or other commercial content you should be concerned. Researchers[3] note that typos, grammar mistakes or lots of hyperlinks can indicate that this email is spam and has no important information.

Eliminate KCTF Locker ransomware related problems 

To remove KCTF Locker ransomware properly and get rid of the damage, you need to be very cautious. Since this is a silent intruder, it may work in the background and change various settings on the device. Use our guide to block the virus and then scan the system using Reimage, Malwarebytes or Plumbytes Anti-MalwareNorton Internet Security to clean the system thoroughly and fix the damage caused by the threat.  

Manual KCTF Locker ransomware removal is not recommended as there are numerous files and components to look after. Then, don't forget to clean up all the damage after the virus termination and restore your encrypted files. To recover this data, you can also rely on methods provided by our experts. 

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More information about this program can be found in Reimage review.

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To remove KCTF Locker virus, follow these steps:

Remove KCTF Locker using Safe Mode with Networking

Reboot your device in Safe Mode with Networking, this way you can disable KCTF Locker ransomware:

  • Step 1: Reboot your computer to Safe Mode with Networking

    Windows 7 / Vista / XP
    1. Click Start Shutdown Restart OK.
    2. When your computer becomes active, start pressing F8 multiple times until you see the Advanced Boot Options window.
    3. Select Safe Mode with Networking from the list Select 'Safe Mode with Networking'

    Windows 10 / Windows 8
    1. Press the Power button at the Windows login screen. Now press and hold Shift, which is on your keyboard, and click Restart..
    2. Now select Troubleshoot Advanced options Startup Settings and finally press Restart.
    3. Once your computer becomes active, select Enable Safe Mode with Networking in Startup Settings window. Select 'Enable Safe Mode with Networking'
  • Step 2: Remove KCTF Locker

    Log in to your infected account and start the browser. Download Reimage or other legitimate anti-spyware program. Update it before a full system scan and remove malicious files that belong to your ransomware and complete KCTF Locker removal.

If your ransomware is blocking Safe Mode with Networking, try further method.

Remove KCTF Locker using System Restore

Use System Restore feature if you want to get rid of this threat by disabling it:

  • Step 1: Reboot your computer to Safe Mode with Command Prompt

    Windows 7 / Vista / XP
    1. Click Start Shutdown Restart OK.
    2. When your computer becomes active, start pressing F8 multiple times until you see the Advanced Boot Options window.
    3. Select Command Prompt from the list Select 'Safe Mode with Command Prompt'

    Windows 10 / Windows 8
    1. Press the Power button at the Windows login screen. Now press and hold Shift, which is on your keyboard, and click Restart..
    2. Now select Troubleshoot Advanced options Startup Settings and finally press Restart.
    3. Once your computer becomes active, select Enable Safe Mode with Command Prompt in Startup Settings window. Select 'Enable Safe Mode with Command Prompt'
  • Step 2: Restore your system files and settings
    1. Once the Command Prompt window shows up, enter cd restore and click Enter. Enter 'cd restore' without quotes and press 'Enter'
    2. Now type rstrui.exe and press Enter again.. Enter 'rstrui.exe' without quotes and press 'Enter'
    3. When a new window shows up, click Next and select your restore point that is prior the infiltration of KCTF Locker. After doing that, click Next. When 'System Restore' window shows up, select 'Next' Select your restore point and click 'Next'
    4. Now click Yes to start system restore. Click 'Yes' and start system restore
    Once you restore your system to a previous date, download and scan your computer with Reimage and make sure that KCTF Locker removal is performed successfully.

Bonus: Recover your data

Guide which is presented above is supposed to help you remove KCTF Locker from your computer. To recover your encrypted files, we recommend using a detailed guide prepared by security experts.

If your files are encrypted by KCTF Locker, you can use several methods to restore them:

Data Recovery Pro can restore accidentally deleted or encrypted files

Use Data Recovery Pro and restore files encrypted by ransomware

  • Download Data Recovery Pro;
  • Follow the steps of Data Recovery Setup and install the program on your computer;
  • Launch it and scan your computer for files encrypted by KCTF Locker ransomware;
  • Restore them.

Windows Previous Versions feature can recover your files after the ransomware attack

If System Restore feature was enabled, you could try data recovery using Windows Previous Versions

  • Find an encrypted file you need to restore and right-click on it;
  • Select “Properties” and go to “Previous versions” tab;
  • Here, check each of available copies of the file in “Folder versions”. You should select the version you want to recover and click “Restore”.

ShadowExplorer restores files from Shadow Volume Copies

If KCTF Locker ransomware left Shadow Volume Copies uncouched, use ShadowExplorer

  • Download Shadow Explorer (;
  • Follow a Shadow Explorer Setup Wizard and install this application on your computer;
  • Launch the program and go through the drop down menu on the top left corner to select the disk of your encrypted data. Check what folders are there;
  • Right-click on the folder you want to restore and select “Export”. You can also select where you want it to be stored.

Decryption is not possible as there is no official decryptor for this virus yet.

About the author

Gabriel E. Hall
Gabriel E. Hall - Passionate web researcher

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