Kuus Virus


Kuus is a ransomware cryptovirus that targets most popular file types on the computers of its victims. Kuus encodes these files using a complex encryption algorithm, thus robbing users of access to said files.

Kuus Virus

The Kuus Virus ransom message

This is all part of virtual blackmail scheme that originated back in the late 80’s and has been going strong since. The idea behind it is that your files are basically held ‘hostage’ by the hackers in charge of the ransomware attack. And in order to ‘free’ them, victim users are required to send a certain amount of money in ‘ransom’. In turn, the way the files are freed is with the help of a special decryption key, which the hackers promise to send as soon as they receive your payment.

However, there are several issues with this deal. For one, there’s no guarantee that you will in fact receive a decryption key, and practice has shown that not everyone does. And for another, the decryption key is unique for each instance of infection. Therefore, it is possible for mixups to occur, and you could easily end up receive the wrong key – which will not do anything to decode your data. Obviously, the criminals don’t do refunds and you can pretty much forget about getting the correct key.

This is why we generally encourage our readers to try and approach this matter using alternative solutions. Unlike what the cybercriminals will have you believe, there are other ways you can potentially regain access to the files that have been locked by Kuus, Repl, Maas or other STOP/Djvu Ransomware. And in the below removal guide, our team has dedicated a separate section specifically to these possible solutions. However, before you attempt any of them, it is vital that you first remove Kuus form your system. This will prevent any further instances of encryption from occurring later on.

The Kuus virus

The Kuus virus is notoriously stealthy and may bypass most antivirus software on the market. This allows the Kuus virus to operate undisturbed, sometimes for hours at a time.

Kuus Virus

The Kuus Virus encrypted files

The encryption process is often a tedious one, as files are generally encrypted one by one. And if your machine doesn’t have the most processing power, and/or if it’s overloaded with data, the whole malicious act may take very long to complete. This may even result in a significant slowdown of your system, which may sometimes prompt victims to investigate what the reason for it may be. And in such cases, it’s possible to intercept the virus by noticing it in your Task Manager, which should, in turn, immediately prompt users to switch off the computer at once and seek professional assistance.

The Kuus file distribution

One of the keys to preventing an attack like this is being aware of the Kuus file distribution channels. And the two most common ways in which in the Kuus file distribution occurs is with the help of spam messages and malvertisements.

Sometimes a Trojan horse virus may be employed to act as a backdoor, so it may be a good idea to scan your system for malware once you’ve removed Kuus.


Name Kuus
Type Ransomware
Danger Level High (Ransomware is by far the worst threat you can encounter)
Symptoms Very few and unnoticeable ones before the ransom notification comes up.
Distribution Method From fake ads and fake system requests to spam emails and contagious web pages.
Data Recovery Tool Not Available
Detection Tool

Remove Kuus Ransomware

Kuus Virus

Some of the steps will likely require you to exit the page. Bookmark it for later reference.

Reboot in Safe Mode (use this guide if you don’t know how to do it).

Kuus Virus


Press CTRL + SHIFT + ESC at the same time and go to the Processes Tab. Try to determine which processes are dangerous. 

Kuus Virus

Right click on each of them and select Open File Location. Then scan the files with our free online virus scanner:

Each file will be scanned with up to 64 antivirus programs to ensure maximum accuracy
This scanner is free and will always remain free for our website's users.
This file is not matched with any known malware in the database. You can either do a full real-time scan of the file or skip it to upload a new file. Doing a full scan with 64 antivirus programs can take up to 3-4 minutes per file.
Kuus Virus
Drag and Drop File Here To Scan
Kuus Virus
Analyzing 0 s
Each file will be scanned with up to 64 antivirus programs to ensure maximum accuracy
    This scanner is based on VirusTotal's API. By submitting data to it, you agree to their Terms of Service and Privacy Policy, and to the sharing of your sample submission with the security community. Please do not submit files with personal information if you do not want them to be shared.

    After you open their folder, end the processes that are infected, then delete their folders. 

    Note: If you are sure something is part of the infection – delete it, even if the scanner doesn’t flag it. No anti-virus program can detect all infections.

    Kuus Virus

    Hold the Start Key and R –  copy + paste the following and click OK:

    notepad %windir%/system32/Drivers/etc/hosts

    A new file will open. If you are hacked, there will be a bunch of other IPs connected to you at the bottom. Look at the image below:

    Kuus Virus

    If there are suspicious IPs below “Localhost” – write to us in the comments.

    Type msconfig in the search field and hit enter. A window will pop-up:

    Kuus Virus

    Go in Startup —> Uncheck entries that have “Unknown” as Manufacturer.

    • Please note that ransomware may even include a fake Manufacturer name to its process. Make sure you check out every process here is legitimate.

    Kuus Virus

    Type Regedit in the windows search field and press EnterOnce inside, press CTRL and F together and type the virus’s Name. 

    Search for the ransomware  in your registries and delete the entries. Be extremely careful –  you can damage your system if you delete entries not related to the ransomware.

    Type each of the following in the Windows Search Field:

    1. %AppData%
    2. %LocalAppData%
    3. %ProgramData%
    4. %WinDir%
    5. %Temp%

    Delete everything in Temp. The rest just check out for anything recently added. Remember to leave us a comment if you run into any trouble!

    Kuus Virus 

    How to Decrypt Kuus files

    We have a comprehensive (and daily updated) guide on how to decrypt your files. Check it out here.

    If the guide doesn’t help, download the anti-virus program we recommended or try our free online virus scanner. Also, you can always ask us in the comments for help!


    About the author


    Violet George

    Violet is an active writer with a passion for all things cyber security. She enjoys helping victims of computer virus infections remove them and successfully deal with the aftermath of the attacks. But most importantly, Violet makes it her priority to spend time educating people on privacy issues and maintaining the safety of their computers. It is her firm belief that by spreading this information, she can empower web users to effectively protect their personal data and their devices from hackers and cybercriminals.


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