How to remove Gatz Ransomware and decrypt .gatz files

What is Gatz Ransomware

Gatz Ransomware is a disastrous virus, that uses AES encryption algorithms to encrypt users’ files. After encoding, files obtain following extensions: .gatz. The malware aims at encryption of personal data, such as documents, photos, videos, music, e-mails. Deep encoding makes those files unapproachable, and decryption instruments available today cannot help in most cases. To start automatically each time the OS starts, the cryptographer creates an entry in the Windows registry key that defines a list of programs that start when the computer is turned on or restarted. To determine which key to use for encryption, Gatz Ransomware tries to establish a network connection with its command server. The virus sends information about the infected computer to the server and receives the encryption key from it. In addition, the command server can send additional commands and modules to the virus that will be executed on the victim’s computer. If the data exchange with the command server was successful, the virus uses the received encryption key (online key). This key is unique for each infected computer. If Gatz Ransomware was unable to establish a connection with its server, a fixed key (offline key) will be used to encrypt files. Below you can observe _readme.txt file (ransom note), that virus places in affected folders:

Malefactors demand a $980 fee for decryption (or $490 if paid in 72 hours). The virus can encrypt all files on the victim’s computer, regardless of where they are located. Files on your computer’s internal drives, connected external devices, and cloud storage can be encrypted. Type of the file and its contents are not important for the virus – any file can be encrypted. The only thing is that the virus does not encrypt files located in Windows system directories. Use virus removal tools, featured in the article, to remove the core of the virus. Once, the virus is removed, you can try STOP Djvu Decryptor from EmsiSoft, the most comprehensive utility to break Gatz Ransomware encryption to date. All standard Windows features to restore files are worth trying, although the threat technically reduces the prospects of a successful outcome. The final step is using file-recovery software. The experience shows, that this can be a workaround, that helps to return the information at least partially. 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. The only option for a successful 100% recovery is using existing backups. Implement the following methods to remove Gatz Ransomware and decrypt .gatz files. If you don’t succeed in decryption today, keep encrypted files on your PC for possible decryption in the future.

How Gatz Ransomware infected your computer

Gatz Ransomware has become increasingly popular over the past few years, with millions victims reported so far. It is spread through malicious emails, websites, and links shared on social media sites. Victims are advised to never pay the ransom as there is no guarantee that their files will be decrypted after payment. Instead, they should use anti-malware software to remove the infection and restore their data from backups if possible.

1. Download Gatz Ransomware Removal Tool
2. Get decryption tool for .gatz 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 Gatz Ransomware

Virus modifies “hosts” file to block Windows updates, downloading antivirus programs, and visiting sites related to security news or offering security solutions. Gatz 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. Gatz 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 Gatz Ransomware are: Emsisoft Anti-Malware and Malwarebytes Anti-Malware.

How to remove Gatz Ransomware manually

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

Gatz Ransomware files:

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

Gatz Ransomware registry keys:

no information

How to decrypt and restore .gatz files

Use automated decryptors

Download STOP Djvu Decryptor from EmsiSoft (.gatz 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 .gatz files, encrypted by Gatz 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 .gatz 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 Gatz 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 .gatz 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 .gatz

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 Gatz 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. Gatz 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