Remove COSAKOS ransomware and recover the encrypted files

Complete COSAKOS ransomware removal instructions

COSAKOS is yet another variant of Djvu/STOP ransomware family. The person who discovered it is Michael Gillespie. Like the preceded viruses of this family, the COSAKOS ransomware encrypts almost all the files making them inaccessible and then demands ransom to be paid to allegedly get the files back. The files encrypted by this ransomware get a unique extension named .COSAKOS (where the name of the virus is derived from). Following to encryption process is done; the ransomware generates a text file named _readme.txt that contains the information about the attack on the computer and instruct victims how to allegedly get back the files.

The _readme.txt basically contains a ransom demanding message. It states that the files are encrypted and that victims need to contact the ransomware developers to get a unique key from them. This is true that the files decryption requires a unique key, as the ransomware encrypts files by using some cipher algorithm that allows the developers to do so. The problem is that this key is hidden behind remote server under controlled of Cyber Criminals with an intention to blackmail the users to pay ransom fee. As the ransom note states, the victims have to purchase a decryption key (embedded with the password). The one who wants that key has to pay to write an email to provided email address. In the email, they can send their 1 encrypted file guaranteed to be decrypted for free as a proof that the decryption tool is really working, written on the ransom note. The decryption tool cost $980. The victims are discounted to 50% on the price if they contact the developers within 72 hours of the files encryption and so the price will drop down to $490. Nevertheless, you must never provide ransom fee to the evil people behind the ransomware not even contact them. Simply ignore the message. To restore the files, rely on some alternate sources. Cyber researcher Gillespie has released a decryption tool. Try to recover the files by using it. If this does not work, the only possible solution is to restore everything from a backup, if there is one created.

How did the ransomware intrude?

Typically, ransomware are distributed via using spam campaigns, Trojans, unofficial software download channels, cracking tools and fake software updaters. Spam campaigns are used to design and distribute deceptive emails consisting of deceptive message encouraging users to click on attachments on them. Such an attachment typically includes MS Office documents, exe files, PDF, or some archives files attached with malicious payload of some malware. The infection occurs when the recipients get tricked and open the attachments. Trojans are malicious applications design to download and install other malicious malware. Untrustworthy software download sources include free file hosting sites, freeware downloaders and installers and P2P networks spread malware by presenting it as legit software. Software cracking tools are usually designed to bypass activation of software that is not free. Unfortunately, in many cases Cyber Criminals design these tools to download and install unwanted applications. Fake software updaters can damage to the system by downloading malicious programs instead of updates.

Threat Summary

Name: COSAKOS ransomware

Type: Ransomware

Symptoms: Files cannot be opened, the previously functioned files appear with different extension name, and ransom payment is demanded

Ransom Amount: $980/$490

Cyber Criminal contact: [email protected], [email protected] or @datarestore (Telegram).

Ransom file: _readme.txt

Extension use: .COSAKOS

Distribution methods: Infected email attachments, torrent sites, malicious ads

Damages: possibly other malicious malware such as password stealing trojan intrude along with the ransomware

Removal: eliminate COSAKOS ransomware by using Spyhunter

How to protect PC from ransomware?

Use official websites for any software downloads, installs and updates. Avoid aforementioned software download sources. Same goes for activation any software as well. Rely on official cracking tools instead of fake one that is meant of causing computer infections. It is important to avoid clicking on any attachments provided on any email if they look irrelevant or the email’s sender address is suspicious. For betterment, use some reputable antivirus tool that provides regular update for the installed applications and firewall security measures and prevents the PC from any big issues.

Full text message presented by _readme.txt:


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:

[email protected]

Reserve e-mail address to contact us:

[email protected]

Our Telegram account:


Mark Data Restore

Your personal ID:

Remove COSAKOS ransomware

Below, step by step COSAKOS ransomware removal instruction is provided for you so that you will not find any trouble when performing the removal process. You have another option for to do the same. Use spyhunter or other reliable antivirus tool and scan the affected with it. The tool scans the PC for viruses and detects and deletes COSAKOS ransomware and all its components.

Recommended Ransomware Removal & File Restoration Guide

COSAKOS ransomware is extremely robust in its nature to encrypt your files, and unless the threat is removed completely, file recovery is technically not possible. To do complete removal of COSAKOS ransomware out of your computer. Downlaod Spyhunter Anti-Spyware Tool Now.

After the infection is completely removed out of your compromised system, you may further process the encrypted file recovery either with your own lately created backup file. Or choose a trusted data recovery program to restore your data. Download a suggested recovery tool.

How to turn your encrypted files working once again?

Well, through the above explanations mentioned, you might have learned actually what happened to your files after encryption. Since the malware that has affected your files is now removed with suggested scanner, you would still require to turn your files working. And we are now going to discuss how to accomplish this task. Based on expert’s researches and their findings, there’s a number of possible methods or ways which a user can get through to restore their encrypted files to work. Even many of victimized users have tried these methods with their own infected computer and success rate is almost 95 percent. So, you can hope to have your files back, and in order to accomplish complete restore of your infected data, we suggest you check out some suggested methods here:

Methods 1: Restore encrypted files using a powerful data recovery software

Before you start to read the steps, you should know this method is appropriate to those users who have found no solutions to decrypt their files affected by ransomware. But still they are able to utilize their system and can install a software. According to experts, this method has very low difficulty level as it utilizes a program to do so.

Although this method is called to be the safest way to recover encrypted files, it still have some limitations. Technically, the encrypted data recovery solution looks through your system and its partitions to recover original files which are actually deleted by virus to replace with the encrypted one. In many cases, the user tend to copy the encrypted files on some external drive and re-install Windows OS that actually declines the chances of data recovery through this method. So, after you have managed to clean your system against malware effects, leave the files as they are and get through the steps to restore your files using one of the top most data recovery app called Stellar Phoenix Data Recovery Software.

Step 1: At first, download the app on your system by clicking the download button below.

Step 2: Click on the downloaded file through your browser to execute its installer.

Step 3: In the license agreement page, click to accept the terms and click Next button. Further, follow on-screen instructions to complete the installation, and click on Finish button finally.

Step 4: After the installation is done, the program will run automatically. At the first interface, select the file types now that you intend to recovery followed by clicking Next.

Step 5: Select the drives over which you need the software to run over and perform the recovery of encrypted files. Done? Click on Scan button.

Step 6: The software will now scan all selected drive to complete the restore process, however it may take some time depending upon volume of drives and number of files or directories were there previously. After the scanning process ends, you will be shown with a file explorer with preview of your data which you want to recover. Just select those which you need to be restored.

Step 7: Browse a location where you want the restored data to be saved.

Method 2: Encrypted file recovery with a lately created Windows backup

This method is technically for those who have a lately created Windows backup saved somewhere and is not affected by the ransomware. Using inbuilt system recovery services, the backup can restore the files which are included under the backup. This method is considered easier as well and leaves no software, thus considered as a very popular method to fight against emergencies caused by infectious malware. Here are the steps to follow:

Step 1: Hit Win + R key combination and to execute Run command line.

Step 2: In the Run text field, type ‘ms-settings:windowsupdate’ and hit the OK button.

Step 3: You will be shown Windows update settings, but you have actually to click Backup option as shown in picture, and located in left pane.

Step 4: Click on ‘More Options’ to open Backup Options panel.

Step 5: As shown in the image below, select or click on “Restore files from a current backup.”

Step 6: In the next shown window, locate the backup where you have saved it, and click on restore button below as marked in the image.

Methods 3: Using Shadow Explorer Application

This file recovery solution is recommended to those who have their backup but is currently not working, still the files under backup are not yet deleted. In this case, Shadow Explorer is an application that can help you restoring your files from those backup files which are active, but still disabled by ransomware somehow. Under this circumstance, inbuilt Windows Backup and Recovery option will not work for you, rather the software will do the magic easily. To accomplish file recovery in this case, get through the steps here mentioned:

Step 1: Click the button below to download Shadow Explorer on your computer.

Step 2: Browser the location where you have downloaded the file. Double click and extract the zip file.

Step 3: Click to open ShadowExplorerPortable directory and double click on the file as shown in the image below.

Step 4: A drop down menu will appear on screen, so just select a desired Date and time according to your requirements on the top left of Shadow Explorer app, and choose the files in given interface that you want to restore using the software. Once the selection is done, Click on the button Export..

Methods 4: Using other decryptors

Well, this method might sounds a bit weird as every ransomware identity basically uses different enciphers and methods to encrypt files on targeted computers. But when the a ransomware which has actually infected your machine comes from a ransomware family for which a decryptor is officially working and available as well, then this might work for you. Technically, this method is just based on luck and analysis, still many users have reported this worked for them. So, if you have seen a ransomware has infected your computer, the very first thing you should do is to identity what kind of virus has actually affected your machine. In most of the cases, ransomware attacks are irreversible, still those infections basically comes from a parent ransomware which might be cracked earlier. For an instance, Scarab ransomware or Hiddentear ransomware are some families which can be decrypted. To check your luck if the present ransomware that has affected your machine is decryptable or not. To do so, follow the guidelines below:

Step 1: Check the Ransomware Database Here and check if decryptor is available for the malware

Step 2: In case you find no results, you can check an open source project called NoMoreRansom to find the ransomware details and decryptor, which has affected your machine. If found, download the decryptor on your computer’s local drive. This page is being regularly updated by its officials once a ransomware is discovered in world.

Step 3: Before you proceed with the downlaoded decryptor, make sure you have backup all your important files.

Step 4: Execute the decryptor to scan and restore your files easily.

Recommended Ransomware Removal & File Restoration Guide

COSAKOS ransomware is extremely robust in its nature to encrypt your files, and unless the threat is removed completely, file recovery is technically not possible. To do complete removal of COSAKOS ransomware out of your computer. Downlaod Spyhunter Anti-Spyware Tool Now.

After the infection is completely removed out of your compromised system, you may further process the encrypted file recovery either with your own lately created backup file. Or choose a trusted data recovery program to restore your data. Download a suggested recovery tool.