GATZ VIRUS (.gatz FILE) RANSOMWARE 🔐 FIX & DECRYPT DATA

Gatz virus is a STOP/DJVU family of ransomware-type infections. This virus encrypts your files (video, photos, documents) that can be tracked by a “.gatz” extension. It uses a strong encryption method, which makes it impossible to calculate the key in any way.

I’ve compiled a comprehensive list of all possible solutions, tips, and practices in neutralizing the Gatz virus, and decrypting files. In some instances, it’s easy to retrieve your files. And sometimes it is just impossible.

Once the Gatz virus is introduced into a computer system and starts to encrypt files, it begins and then adds the “.gatz” extension to the encrypted files. The virus demands a ransom payment in exchange for a key to decrypt the files which will allow the unlocking of encrypted files. In the majority of cases, the ransom note will appear as either a text file “_readme.txt”.

“Gatz” uses a unique code for every victim, with an exception:

• If Gatz is unable to establish a connection with the command and control server (C&C Server) prior to beginning the encryption process, it uses offline keys. This key is the same for all victims, making the possibility of decrypting encrypted files during a ransomware attack.

Is Gatz virus?

☝️ Gatz can be correctly identified as a STOP/DJVU ransomware infection.

The Gatz ransomware is a specific kind of malware that encrypted your files and then forces you to pay to restore them. Note that Djvu/STOP ransomware family was first revealed and analyzed by virus analyst Michael Gillespie.

Gatz virus is similar to other DJVU ransomware like: Xash, Gash, Qore, Qopz. This virus encrypts all popular file types and adds its own “.gatz” extension into all files. For example, the file “1.jpg”, will be changed into “1.jpg.gatz“. As soon as the encryption is accomplished, the virus generates a special message file “_readme.txt” and adds it into all folders that contain the modified files.

The image below gives a clear vision of how the files with “.gatz” extension look like:

Gatz File (STOP/DJVU Ransomware)

This _readme.txt file asking payment is for restoring files via decryption key:

_readme.txt (STOP/DJVU Ransomware) – The scary alert demanding from users to pay the ransom to decrypt the encoded files contains these frustrating warnings

Gatz ransomware arrives as a set of processes that are meant to perform different tasks on a victim’s computer. One of the first ones being launched is winupdate.exe, a tricky process that displays a fake Windows update prompt during the attack. This is meant to convince the victim that a sudden system slowdown is caused by a Windows update. However, at the same time, the ransomware runs another process (usually named after four random characters) which starts scanning the system for target files and encrypting them. Next, the ransomware deletes Volume Shadow Copies from the system using the following CMD command:

vssadmin.exe Delete Shadows /All /Quiet

Once deleted, it becomes impossible to restore the previous computer state using System Restore Points. The thing is, ransomware operators are getting rid of any Windows OS-based methods that could help the victim to restore files for free. In addition, the crooks modify the Windows HOSTS file by adding a list of domains to it and mapping them to the local IP. As a result, the victim will run into a DNS_PROBE_FINISHED_NXDOMAIN error when accessing one of the blocked websites.

We noticed that ransomware attempts to block websites that publish various how-to guides for computer users. It is evident that by restricting specific domains, the crooks are trying to prevent the victim from reaching relevant and helpful ransomware-attack-related information online. The virus also saves two text files on the victim’s computer that provide attack-related details – the victim’s public encryption key and personal ID. These two files are called bowsakkdestx.txt and PersonalID.txt.

After all these modifications, the malware doesn’t stop. Variants of STOP/DJVU tend to drop Vidar password-stealing Trojan on compromised systems. This threat has a lengthy list of capabilities, such as:

• Stealing Steam, Telegram, Skype login/password;
• Stealing cryptocurrency wallets;
• Downloading malware to the computer and running it;
• Stealing browser cookies, saved passwords, browsing history, and more;
• Viewing and manipulating files on victim’s computer;
• Allowing the hackers to perform other tasks on the victim’s computer remotely.

The DJVU/STOP ransomware family utilizes the AES-256 cryptography algorithm. If the ransomware has encrypted your files with an online decryption key, a unique key is necessary to decrypt them. Unfortunately, it is impossible to decrypt the files without this key.

If Gatz was used in online mode, you cannot access the AES-256 key. The criminals who distribute the Gatz virus store the key on a remote server.

To obtain the decryption key, you must pay $980. The message encourages victims to contact the frauds via email ([email protected]) to obtain payment details.

The message by the ransomware states the following information:

ATTENTION!

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:

https://we.tl/t-WJa63R98Ku

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]

Your personal ID:
XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX

Do not pay for Gatz!

Please, try to use the available backups, or Decrypter tool

_readme.txt file also indicates that the computer owners must get in touch with the Gatz representatives within 72 hours starting from the moment of files were encrypted. On the condition of getting in touch within 72 hours, users will be granted a 50% rebate. Thus the ransom amount will be minimized to $490). Yet, stay away from paying the ransom!

I strongly recommend that you do not contact these crooks and do not pay. One of the most real working solutions to recover lost data – just using the available backups, or using Decrypter tool.

All such viruses apply a similar set of actions to generate the unique decryption key required to recover the ciphered data. Therefore, manual recovery of the ciphered data is impossible unless the ransomware is still in the development stage or has some hard-to-track flaws. Regularly backing up your crucial files is the only solution to prevent the loss of valuable data.

It should be noted that even if backups are maintained regularly, they must be stored in a specific location without loitering, and not connected to the main workstation. For example, the backup may be kept on a USB flash drive or an alternative external hard drive storage. Alternatively, the help of online (cloud) information storage can be referred to.

It is needless to mention that when backup data is maintained on a common device, it may also be ciphered like other data. For this reason, locating the backup on the main PC is surely not a wise idea.

How I was infected?

Ransomware has various methods to build into your system. But it doesn’t really matter what method had a place in your case.

Gatz attack following a successful phishing attempt.

How To Remove Gatz Virus?

In addition to encoding a victim’s files, the Gatz infection has also started to install the Vidar Stealer on the system to steal account credentials, cryptocurrency wallets, desktop files, and more.³

Reasons why I would recommend GridinSoft⁴

1. Run the setup file.

   
   

2. Press the “Install” button.

   

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

   

4. Wait for complete.

   

5. Click on “Clean Now”.