How to remove QolkuzNbVcG ransomware from the operating system?

Also Known As: QolkuzNbVcG virus
Distribution: Moderate
Damage level: Severe

QolkuzNbVcG ransomware removal instructions

What is QolkuzNbVcG?

QolkuzNbVcG is the name of a malicious program, belonging to the Xorist ransomware family. This malware operates by encrypting data in order to demand payment for the decryption. During the encryption process, all of the affected files are appended with the ".QolkuzNbVcG" extension. For example, a file originally tilted something like "1.jpg" would appear as "1.jpg.QolkuzNbVcG" - following encryption. After this process is complete a ransom note is presented in a pop-up window and text file - "HOW TO DECRYPT FILES.txt" - that is created in every compromised folder. The ransom-demanding message is incomplete, due to this - it is highly likely that QolkuzNbVcG is still in development.

The ransom-demanding messages in the pop-up window and text file ("HOW TO DECRYPT FILES.txt") are identical. It states that all of the victims' data has been encrypted. To recover their files, they are instructed to establish contact with the cyber criminals behind the infection, via SMS messages. Additionally, their text messages must include a unique ID. However, neither the criminals' number nor the ID are provided, despite the formatting of the note suggesting that they should be. Users are warned that they have a limited amount of times they can enter the decryption key; much like with the other missing information - the number of possible attempts is absent as well. After this unspecified number has been exceeded, the data will be damaged beyond repair. The message ends by alerting users that they should exercise caution when entering the decryption key. In many cases of ransomware attacks, decryption is impossible without interference of the cyber criminals responsible. Recovery might be possible, if the malicious program has significant bugs/flaws. Even if the ransom demands are properly made, it is expressly advised against paying criminals. Since often, despite meeting their demands - victims do not receive the promised decryption keys/tools. Therefore, users experience financial loss and their data remains encrypted and worthless. To prevent QolkuzNbVcG from further encryptions, it must be removed from the operating system. Unfortunately, removal will not restore already affected files. The only viable solution is recovering them from a backup, if one was created prior to the infection and was stored in a separate location.

Screenshot of a message encouraging users to pay a ransom to decrypt their compromised data:

QolkuzNbVcG decrypt instructions (pop-up)

ZeronineGlUTe and Kupidon are a couple examples of other ransomware-type programs. They are designed to encrypt data and demand ransoms for the decryption tools/software. There are two main differences in-between them: the cryptographic algorithms they use (symmetric or asymmetric) and size of the demanded payment. Cyber criminals tend to prefer digital currencies (e.g. cryptocurrencies, pre-paid vouchers, etc.), due to transactions of them being difficult/impossible to trace. To avoid data loss, it is highly recommended to keep backups in remote servers and/or unplugged storage devices. It is best to keep backups in multiple different locations.

How did ransomware infect my computer?

Ransomware and other malware are primarily proliferated through trojans, spam campaigns, illegal activation tools ("cracks"), illegitimate updates and untrustworthy download channels. Trojans are malicious programs with varied functionalities, which can include the ability to cause chain infections (i.e. download/install additional malware). Spam campaigns are used to send thousands of deceptive/scam emails. These letters contains malicious content, in the shape of attachments and/or download links. The malicious files can be in various formats (e.g. archive and executable files, Microsoft Office and PDF documents, JavaScript, etc.); when they are executed, run or otherwise opened - the infection process is initiated. Rather than activate licensed product, illegal activation ("cracking") tolls can download/install malware. Systems are infected through fake updaters by them exploiting flaws of outdated products and/or by simply installing malicious software instead of the promised updates. Malware can be unintentionally downloaded from dubious sources, e.g. unofficial and free file-hosting websites, Peer-to-Peer sharing networks and other third party downloaders.

Threat Summary:
Name QolkuzNbVcG virus
Threat Type Ransomware, Crypto Virus, Files locker
Encrypted Files Extension .QolkuzNbVcG
Ransom Demanding Message Text presented in the pop-up and HOW TO DECRYPT FILES.txt
Detection Names Avast (Win32:Dh-A [Heur]), BitDefender (Trojan.Ransom.AIG), ESET-NOD32 (A Variant Of Win32/Filecoder.Q), Kaspersky (Trojan-Ransom.Win32.Xorist.ln), Full List Of Detections (VirusTotal)
Symptoms Cannot open files stored on your computer, previously functional files now have a different extension (for example, my.docx.locked). A ransom demand message is displayed on your desktop. Cyber criminals demand payment of a ransom (usually in bitcoins) to unlock your files.
Distribution methods Infected email attachments (macros), torrent websites, malicious ads.
Damage All files are encrypted and cannot be opened without paying a ransom. Additional password-stealing trojans and malware infections can be installed together with a ransomware infection.
Malware Removal (Windows)

To eliminate possible malware infections, scan your computer with legitimate antivirus software. Our security researchers recommend using Malwarebytes.
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How to protect yourself from ransomware infections?

Suspicious and/or irrelevant emails should not be opened, especially any attachments or links present in dubious mail - as doing so can result in a severe system infection. All downloads should be done only from official and verified sources. Additionally, it is recommended to always activate and update products with tools/functions, provided by genuine developers. Illegal activation ("cracking") tools and third party updaters are advised against use, as they often cause malware infections. To ensure device and user safety, it is crucial to have a dependable anti-virus/anti-spyware installed. Furthermore, this software must be kept up-to-date, used to run regular system scans and to remove detected/potential threats. If your computer is already infected with QolkuzNbVcG, we recommend running a scan with Malwarebytes for Windows to automatically eliminate this ransomware.

Text presented in QolkuzNbVcG ransomware's ransom note:

Attention! All your files are encrypted!
To restore your files and access them,
please send an SMS with the text XXXX to YYYY number.


You have N attempts to enter the code.
When that number has been exceeded,
all the data irreversibly is destroyed.
Be careful when you enter the code!

Screenshot of QolkuzNbVcG's text file ("HOW TO DECRYPT FILES.txt"):

QolkuzNbVcG ransomware text file (HOW TO DECRYPT FILES.txt)

Screenshot of files encrypted by QolkuzNbVcG (".QolkuzNbVcG" extension):

Files encrypted by QolkuzNbVcG ransomware (.QolkuzNbVcG extension)

QolkuzNbVcG ransomware removal:

Instant automatic malware removal: Manual threat removal might be a lengthy and complicated process that requires advanced computer skills. Malwarebytes is a professional automatic malware removal tool that is recommended to get rid of malware. Download it by clicking the button below:
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Quick menu:

Step 1

Windows XP and Windows 7 users: Start your computer in Safe Mode. Click Start, click Shut Down, click Restart, click OK. During your computer start process, press the F8 key on your keyboard multiple times until you see the Windows Advanced Option menu, and then select Safe Mode with Networking from the list.

Safe Mode with Networking

Video showing how to start Windows 7 in "Safe Mode with Networking":

Windows 8 users: Start Windows 8 is Safe Mode with Networking - Go to Windows 8 Start Screen, type Advanced, in the search results select Settings. Click Advanced startup options, in the opened "General PC Settings" window, select Advanced startup. Click the "Restart now" button. Your computer will now restart into the "Advanced Startup options menu". Click the "Troubleshoot" button, and then click the "Advanced options" button. In the advanced option screen, click "Startup settings". Click the "Restart" button. Your PC will restart into the Startup Settings screen. Press F5 to boot in Safe Mode with Networking.

Windows 8 Safe Mode with networking

Video showing how to start Windows 8 in "Safe Mode with Networking":

Windows 10 users: Click the Windows logo and select the Power icon. In the opened menu click "Restart" while holding "Shift" button on your keyboard. In the "choose an option" window click on the "Troubleshoot", next select "Advanced options". In the advanced options menu select "Startup Settings" and click on the "Restart" button. In the following window you should click the "F5" button on your keyboard. This will restart your operating system in safe mode with networking.

windows 10 safe mode with networking

Video showing how to start Windows 10 in "Safe Mode with Networking":

Step 2

Log in to the account infected with the QolkuzNbVcG virus. Start your Internet browser and download a legitimate anti-spyware program. Update the anti-spyware software and start a full system scan. Remove all entries detected.

If you cannot start your computer in Safe Mode with Networking, try performing a System Restore.

Video showing how to remove ransomware virus using "Safe Mode with Command Prompt" and "System Restore":

1. During your computer start process, press the F8 key on your keyboard multiple times until the Windows Advanced Options menu appears, and then select Safe Mode with Command Prompt from the list and press ENTER.

Boot your computer in Safe Mode with Command Prompt

2. When Command Prompt mode loads, enter the following line: cd restore and press ENTER.

system restore using command prompt type cd restore

3. Next, type this line: rstrui.exe and press ENTER.

system restore using command prompt rstrui.exe

4. In the opened window, click "Next".

restore system files and settings

5. Select one of the available Restore Points and click "Next" (this will restore your computer system to an earlier time and date, prior to the QolkuzNbVcG ransomware virus infiltrating your PC).

select a restore point

6. In the opened window, click "Yes".

run system restore

7. After restoring your computer to a previous date, download and scan your PC with recommended malware removal software to eliminate any remaining QolkuzNbVcG ransomware files.

To restore individual files encrypted by this ransomware, try using Windows Previous Versions feature. This method is only effective if the System Restore function was enabled on an infected operating system. Note that some variants of QolkuzNbVcG are known to remove Shadow Volume Copies of the files, so this method may not work on all computers.

To restore a file, right-click over it, go into Properties, and select the Previous Versions tab. If the relevant file has a Restore Point, select it and click the "Restore" button.

Restoring files encrypted by CryptoDefense

If you cannot start your computer in Safe Mode with Networking (or with Command Prompt), boot your computer using a rescue disk. Some variants of ransomware disable Safe Mode making its removal complicated. For this step, you require access to another computer.

To regain control of the files encrypted by QolkuzNbVcG, you can also try using a program called Shadow Explorer. More information on how to use this program is available here.

shadow explorer screenshot

To protect your computer from file encryption ransomware such as this, use reputable antivirus and anti-spyware programs. As an extra protection method, you can use programs called HitmanPro.Alert and EasySync CryptoMonitor, which artificially implant group policy objects into the registry to block rogue programs such as QolkuzNbVcG ransomware.

Note that Windows 10 Fall Creators Update includes a "Controlled Folder Access" feature that blocks ransomware attempts to encrypt your files. By default, this feature automatically protects files stored in the Documents, Pictures, Videos, Music, Favorites, and Desktop folders.

Controll Folder Access

Windows 10 users should install this update to protect their data from ransomware attacks. Here is more information on how to get this update and add an additional protection layer from ransomware infections.

HitmanPro.Alert CryptoGuard - detects encryption of files and neutralises any attempts without need for user-intervention:

hitmanproalert ransomware prevention application

Malwarebytes Anti-Ransomware Beta uses advanced proactive technology that monitors ransomware activity and terminates it immediately - before reaching users' files:

malwarebytes anti-ransomware

  • The best way to avoid damage from ransomware infections is to maintain regular up-to-date backups. More information on online backup solutions and data recovery software Here.

Other tools known to remove QolkuzNbVcG ransomware:

About the author:

Tomas Meskauskas

Tomas Meskauskas - expert security researcher, professional malware analyst.

I am passionate about computer security and technology. I have an experience of over 10 years working in various companies related to computer technical issue solving and Internet security. I have been working as an author and editor for since 2010. Follow me on Twitter and LinkedIn to stay informed about the latest online security threats. Contact Tomas Meskauskas.

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Malware activity

Global malware activity level today:

Medium threat activity

Increased attack rate of infections detected within the last 24 hours.

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QolkuzNbVcG virus QR code
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