How to remove Qoqa Ransomware and decrypt .qoqa files

What is Qoqa Ransomware

Qoqa Ransomware (that is a part of a large family of STOP/Djvu Ransomware) is an obnoxious virus, that encrypts files on computers using the AES encryption algorithm, makes them unavailable, and demands money in exchange for so-called “decryptor”. Files processed by the latest version of STOP Ransomware, in particular, can be distinguished by .qoqa extensions. The analysis showed that the cryptographic installer loaded with the “crack” or adware is installed under an arbitrary name in the %LocalAppData%\ folder. When executed, it loads four executable files there: 1.exe, 2.exe, 3.exe and updatewin.exe. The first of them is responsible for neutralizing Windows Defender, the second is for blocking access to information security sites. After the malware is launched, a fake message appears on the screen that says about installing the update for Windows. In fact, at this moment, almost all user files on the computer are encrypted. In each folder containing encrypted documents, a text file (_readme.txt) appears, in which attackers explain the operation of the virus. They offer to pay them a ransom for decryption, urging them not to use third-party programs, as this can lead to the deletion of all documents. Here is the content of the ransom note:

Unfortunately, chances of successful file recovery are low, because the virus uses advanced mechanisms to prevent the possibility of data restoration. Security researcher Michael Gillespie released a tool called STOP Djvu Decryptor, that was able to retrieve the key for previous versions of STOP Ransomware. However, it is operable only when an offline key was used. At the moment, files with .qoqa extensions cannot be decrypted with STOP Djvu Decryptor. Developers from various security companies working hard on trying to break virus algorithms, and we still provide links and instructions for this instrument. Until this happens you can try standard Windows system functions, such as restore points, shadow copies, previous versions of files, which can be useful, although, malicious algorithms often prevent such opportunities. Stellar Data Recovery Professional is one of the best file-recovery tools and, if used properly, may recover copies and duplicates of encrypted files, that were removed prior to infection. Follow step-by-step instructions in this tutorial to remove Qoqa Ransomware and decrypt .qoqa files for free.

How Qoqa Ransomware infected your computer

1. Download Qoqa Ransomware Removal Tool
2. Get decryption tool for .qoqa files
3. Recover encrypted files with Stellar Data Recovery Professional
4. Restore encrypted files with Windows Previous Versions
5. Restore files with Shadow Explorer
6. Restore media files with Media Repair
7. How to protect from threats like Qoqa Ransomware

Virus modifies “hosts” file to block Windows updates, downloading antivirus programs, and visiting sites related to security news or offering security solutions. Qoqa Ransomware comes along with AZORult trojan, which was initially created to steal logins and passwords. The process of infection also looks like installing Windows updates, the malware shows a fake window, that mimics the update process.

It uses rdpclip.exe to replace a legal Windows file and to launch an attack on a computer network. After encrypting the files, the encrypter is deleted using the delself.bat command file. Qoqa Ransomware virus is propagated via spam attack with malicious e-mail attachments and using manual PC hacking. Can be distributed by hacking through an unprotected RDP configuration, fraudulent downloads, exploits, web injections, fake updates, repackaged, and infected installers. The virus assigns a certain ID to the victims, which is used to name those files and supposedly to send a decryption key. Great tools to protect against Qoqa Ransomware are: Emsisoft Anti-Malware and Malwarebytes Anti-Malware.

How to remove Qoqa Ransomware manually

It is not recommended to remove Qoqa Ransomware manually, for safer solution use Removal Tools instead.

Qoqa Ransomware files:

_readme.txt
rdpclip.exe
delself.bat
{randomname}.exe

Qoqa Ransomware registry keys:

no information

How to decrypt and restore .qoqa files

Use automated decryptors

Download STOP Djvu Decryptor from EmsiSoft (.qoqa variations)

IMPORTANT: Read this detailed guide on using STOP Djvu Decryptor to avoid file corruption and time wasting.

STOP Djvu Decryptor is able to decrypt .qoqa files, encrypted by Qoqa Ransomware. This tool was developed by EmsiSoft. It works in automatic mode, but in most cases works only for files encrypted with offline keys. Download it here:

Download STOP Djvu Decryptor

Dr.Web Rescue Pack

Famous antivirus vendor Dr. Web provides free decryption service for the owners of its products: Dr.Web Security Space or Dr.Web Enterprise Security Suite. Other users can ask for help in the decryption of .qoqa files by uploading samples to Dr. Web Ransomware Decryption Service. Analysis of files will be performed free of charge and if files are decryptable, all you need to do is purchase a 2-year license of Dr.Web Security Space worth $120 or less. Otherwise, you don’t have to pay.

If you are infected with Qoqa Ransomware and removed it from your computer, you can try decrypting your files. Antivirus vendors and individuals create free decryptors for some crypto-lockers. To attempt to decrypt them manually you can do the following:

Use Stellar Data Recovery Professional to restore .qoqa files

1. Download Stellar Data Recovery Professional.
2. Click Recover Data button.
3. Select type of files you want to restore and click Next button.
4. Choose location where you would like to restore files from and click Scan button.
5. Preview found files, choose ones you will restore and click Recover.

Download Stellar Data Recovery Professional

Using Windows Previous Versions option:

1. Right-click on infected file and choose Properties.
2. Select Previous Versions tab.
3. Choose particular version of the file and click Copy.
4. To restore the selected file and replace the existing one, click on the Restore button.
5. In case there is no items in the list choose alternative method.

Using Shadow Explorer:

1. Download Shadow Explorer program.
2. Run it and you will see screen listing of all the drives and the dates that shadow copy was created.
3. Select the drive and date that you want to restore from.
4. Right-click on a folder name and select Export.
5. In case there are no other dates in the list, choose alternative method.

If you are using Dropbox:

1. Login to the DropBox website and go to the folder that contains encrypted files.
2. Right-click on the encrypted file and select Previous Versions.
3. Select the version of the file you wish to restore and click on the Restore button.

Use Media Repair to decrypt media files encrypted with .qoqa

1. Download Media Repair tool.
2. Right-click on the downloaded archive, and select Extract to Media_Repair\.
3. Then double-click on the extracted .exe file to launch the utility.
4. At first, you have to choose which file type you want to decrypt. You can do it from the drop-down menu in the utility.
5. Next, browser the folder with encrypted or reference files. Choose any of them and click on the Test icon located in the top right corner.
6. Media Repair will display a pop-up message with information on whether it can repair the selected file or not.
7. After checking if it is possible or not, select your reference file and click on the icon right under the Test button we used in step #5.
8. If the file pair is properly matched, you can move on and hit the Play button to start repairing. You can also stop the process anytime by clicking on the Stop button.

How to protect computer from viruses, like Qoqa Ransomware, in future

1. Get special anti-ransomware software

Use ZoneAlarm Anti-Ransomware

Famous antivirus brand ZoneAlarm by Check Point released a comprehensive tool, that will help you with active anti-ransomware protection, as an additional shield to your current protection. The tool provides Zero-Day protection against ransomware and allows you to recover files. ZoneAlarm Anti-Ransomware is compatible with all other antiviruses, firewalls, and security software except ZoneAlarm Extreme (already shipped with ZoneAlarm Anti-Ransomware) or Check Point Endpoint products. The killer features of this application are: automatic file recovery, overwrite protection that instantly and automatically recovers any encrypted files, file protection that detects and blocks even unknown encryptors.

Download ZoneAlarm Anti-Ransomware

2. Back up your files

As an additional way to save your files, we recommend online backup. Local storage, such as hard drives, SSDs, flash drives, or remote network storage can be instantly infected by the virus once plugged in or connected to. Qoqa Ransomware uses some techniques to exploit this. One of the best services and programs for easy automatic online backup is iDrive. It has the most profitable terms and a simple interface. You can read more about iDrive cloud backup and storage here.

Download iDrive

3. Do not open spam e-mails and protect your mailbox

Malicious attachments to spam or phishing e-mails are the most popular method of ransomware distribution. Using spam filters and creating anti-spam rules is good practice. One of the world leaders in anti-spam protection is MailWasher Pro. It works with various desktop applications and provides a very high level of anti-spam protection.

Download MailWasher Pro