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Mosk Virus Removal Guide (+Decrypt .mosk files)

Mosk Virus Ransomware

Mosk is a malicious software functioning as common ransomware. Michael Gillespie, the popular virus researcher, first discovered this new name in the DJVU ransomware family.

Mosk was developed for the sole function to encrypt all popular file types. Logically, as soon as the encryption is successfully accomplished, the users are unable to get access to them. Mosk virus adds its own “.mosk” to all the encrypted data. For example, the file “price_list.xls”, as soon as modified by Mosk, will be titled as “price_list.xls.mosk”. Once the file encryption is accomplished, Mosk puts its own special text file (_readme.txt) into all the folders that keep the encrypted files.

The message stated by text file asking for the random os very similar to the notices given by other ransomware hazards belonging to the DJVU family. The caution generally indicates that the data has been encrypted and the only option to get access to it is to use an unique standalone key. Regretfully, this statement is definitely true.

The technique to secure the files utilized by Mosk is not completely investigated. Nevertheless, there is no doubt that each computer system owner may be released an unique decryption key, which is definitely special. It is extremely tough to recover the information without the suitable key in location.

“Don’t worry, you can return all your files!”, from _readme.txt message:

message from Mosk virus

One more peculiarity of the Mosk virus is that the users are not able to get access to the key. The decrypting key is hosted on an unique server under the total control by the scoundrels who have released the Mosk infection into the world wide web. In order to obtain the key and restore the important data, the users are informed to get in touch with the frauds by means of e-mail or by telegram and to pay the ransom in the amount of $980.

The message also states that the people ought to call the Mosk authors within 72 hours upon the moment of the information encryption. The alert indicates that by doing so the people will get a 50% discount rate, for that reason, the ransom quantity falls to $490.

No matter what the amount of the ransom is, we highly encourage that you do not pay the ransom. There is no assurance that these online criminals will keep their guarantees, so they may not care at all what the victims feel about the encryption, even when the amount of the ransom is received into their accounts. Thus, paying ransom often does not result in an effective healing. So, the users may just lose their money for nothing.

Likewise, we advise you not to call the frauds as they instruct. Do not transfer money into their wallets. There are no applications that might split the Mosk virus or restore the information at no charge. For that reason, the only appropriate choice is to bring back the information from possible backups (if available).

Virus Summary

NameMosk Ransomware
File Extensionmosk
Short DescriptionThe ransomware encrypts all the data stored on your system and requires a ransom to be paid on your part supposedly to recover your important files.
SymptomsFile encryption by the ransomware is performed by means of the AES-256 algorithm (CFB mode) encryption algorithm. Once the encryption is completed, the ransomware adds its special .mosk extension to all the files modified by it.
Distribution MethodAdware bundles and software cracks
Similar InfectionsToec, Meka, Craw
Removal Tool   GridinSoft Anti-Malware

Do not forget that the Internet is now loaded with infections similar to the Mosk ransomware. For example, this particular hazard is basically similar to Brusaf and other ransomware-type infections. These destructive energies have actually been developed in order to encrypt the important information and express the demand for the users to pay the ransom. All these infections utilize the similar algorithm to create the specific key for effective files decryption.

Unless the Mosk ransomware is still under the development procedure or has actually got some hidden bugs, it is not possible to restore the information by hand. Hence, the only working solution to avoid the loss of your important data is to routinely preserve current backups of all your important documents.

Another crucial piece of guidance is to keep the backups on special storage not linked to your primary device. For instance, you might store it on the USB Flash Drive, or some external hard disk drive, or by using the cloud data storage services. Keeping the backups on your regular drive is extremely risky, given that the backup might also be encrypted by the Mosk .

Leaks for the Mosk ransomware attack.

Mosk uses lots of paths to penetrate the susceptible computers. It is not certain what particular approach was used in your case, nevertheless, the invasion may occur via the following channels:

  • bundling with third-party programs, primarily free apps;
  • spam e-mails from the unidentified senders;
  • websites offering free hosting;
  • P2P (peer-to-peer) torrent software.

There are times when the Mosk may disguise itself as some authentic application, for example, through the misleading informs requiring setup of some software application upgrade. This is the most common trick used by the frauds to inject the Mosk virus files into the system. In this manner users partially take part in its setup, without plainly comprehending the danger.

Moreover, the scams may send out unsolicited spam e-mail with difficult notifies encouraging individuals to open suspicious attachments or click some download links, for instance, those encouraging the people to open certain photos, text files, tax documents and other info.

No doubt, opening these files or clicking the destructive links may essentially harm the system. Fake Adobe Flash Player update notices may result in the Mosk ransomware seepage. Similarly, downloading the split software may additionally consist of the ransomware installer. The last but not the least, installation of Mosk may occur through some Trojan horses that might be set up stealthily into the system and without the user’s direct permission or perhaps consent.

Avoiding the Mosk attack.

Obviously, there is no outright warranty that your computer system will be always devoid of any malware attacks, however, we wish to share some helpful ideas with you to make it more secure. Make sure to pay very close attention while browsing the web and specifically while getting cost-free programs. Do not open any suspicious e-mail attachments, particularly if the sender is not understood to you.

Do not forget that certain freeware installer may also contain some other extra apps in the bundle. These additional applications might be very harmful. It is of utmost significance to keep your anti-virus software application and your operating system in basic to be constantly correctly upgraded.

It is rather rational that downloading cracked programs is illegal, nevertheless, furthermore, such unapproved apps use might also bring severe damage to your system. For this reason, do not download any cracked programs. Plus, the truth that your existing anti-virus did not safeguard the system from the Mosk ransomware is an excellent factor for you to reevaluate your choices and change to another program that can render the securing functions on a far better level.

Below please find the quotation from the Mosk text file:

 Don't worry, you can return all your files!
 All your files like photos, databases, documents and other important are encrypted with strongest encryption and unique key.
 The only method of recovering files is to purchase decrypt tool and unique key for you.
 This software will decrypt all your encrypted files.
 What guarantees you have?
 You can send one of your encrypted file from your PC and we decrypt it for free.
 But we can decrypt only 1 file for free. File must not contain valuable information.
 You can get and look video overview decrypt tool:
 Price of private key and decrypt software is $980.
 Discount 50% available if you contact us first 72 hours, that's price for you is $490.
 Please note that you'll never restore your data without payment.
 Check your e-mail "Spam" or "Junk" folder if you don't get answer more than 6 hours.
 To get this software you need write on our e-mail:
 Reserve e-mail address to contact us:
 Our Telegram account:

Screenshot of files with “.mosk” extension added by the virus:”

Mosk Ransomware - encrypt files with .mosk extension

Use GridinSoft Anti-Malware to remove Mosk ransomware from your computer

1.Download GridinSoft Anti-Malware.

You can get GridinSoft Anti-Malware by clicking the button below:

  GridinSoft Anti-Malware

2. Double-click on the setup file.

When setup file has finished downloading, double-click on the setup-antimalware-ag.exe file to install GridinSoft Anti-Malware on your computer.
GridinSoft Anti-Malware
An User Account Control asking you about to allow GridinSoft Anti-Malware to make changes to your device. So, you should click “Yes” to continue with the installation.
GridinSoft Anti-Malware Setup

3. Press Install button for run GridinSoft Anti-Malware.

GridinSoft Anti-Malware Install

3.Once installed, GridinSoft Anti-Malware will automatically run.

GridinSoft Anti-Malware  Start

4. Wait for the GridinSoft Anti-Malware scan to complete.

GridinSoft Anti-Malware will automatically start scanning your computer for Win Speedup 2018 and other malicious programs. This process can take a 20-30 minutes, so we suggest you periodically check on the status of the scan process.
GridinSoft Anti-Malware Scan

5. Click on “Clean Now”.

When the scan has completed, you will see the list of infections that GridinSoft Anti-Malware has detected. To remove them click on the “Clean Now” button in right corner.
GridinSoft Anti-Malware Scan Result

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About Daniel Zimmermann

Daniel Zimmermann has been writing on security and malware subjects for many years and has been working in the security industry for over 10 years. Daniel was educated at the Saarland University in Saarbrücken, Germany and currently lives in New York.

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  1. After clean, you have to pay 40$ to clean it up.

  2. Good Morning, Someone can help me , I got this Virus .mosk, i dont what can i do for recover the files

    • Recovering of files is close to impossible (I hope not) but if its an online key less chance. If an offline key then u might have some chance in recovering of files.

      To check if offline, the readme file in c drive mentions the personal id number. If it ends with t1 then if an offline key if any other then online (just like mine)

      Also check emisoft decryptor tool if that’ll help you. It didnt help me though 🙁

  3. Dear Daniel,

    My system appears clean from the ransomware .MOSK but files are still encrypted.

    The key they used to encrypt is an online key, which most of the tech savvy people say is impossible to retrieve files.

    Without any back up I am left with no other options but to pay the freaks!

    Have emailed them but with no answer. ANY HELP just to get back my files, this is so frustrating.

    Any solutions in the future? or no chance at all?

  4. dear daniel,
    my computer has been infected with a mosaic virus since November 7, 2019,
    I have scanned it with malwarebytes and I have decrypted it with emisoft but it didn’t work,

    Don’t worry, you can return all your files!
    All your files like photos, databases, documents and other important are encrypted with the strongest encryption and unique key.
    The only method of recovering files is to purchase the decrypt tool and unique key for you.
    This software will decrypt all your encrypted files.
    What guarantees you have?
    You can send one of your encrypted files from your PC and we decrypt it for free.
    But we can decrypt only 1 file for free. File must not contain valuable information.
    You can get and look at the video overview decrypt tool:
    Price of private key and decrypt software is $ 980.
    50% discount available if you contact us first 72 hours, that’s the price for you is $ 490.
    Please note that you will never restore your data without payment.
    Check your e-mail “Spam” or “Junk” folder if you don’t get answer more than 6 hours.

    To get this software you need to write on our e-mail:

    Reserve your e-mail address to contact us:

    Your personal ID:

    can you help me?

  5. I mean ransomware = .mosk

  6. Its not working, is there any other option

  7. Digão Rodrigo Lucas Petrângelo

    tambem preciso de ajuda para recuperar

  8. My data files have infected by mosk ransomware 4 days ago. But, i found a directory is different from the other infected directory. I found original files and infected files in the same infected directory, i think it was happend because of shutting down system while mosk ransomware was being encryted files,

    I can give these files to ransomware decryptor development for investigation.

    May be it can help to find out to create new decryptor mosk ransomware.

  9. Please I also got infected since 10th Nov 2019. so am among all that really need help from to get away from all these hackers that have encrypted our Files with .Mosk. Because right now I cannot afford the huge some this people are asking for. We really need a more affordable decryption software. Just in case anyone know, kindly let me know the link.

  10. Its not working, is there any other option
    hi send .mosk file decryptor soft

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