How to remove Boza Ransomware and decrypt .boza files

What is Boza Ransomware

Boza Ransomware is a new variant of the STOP/Djvu Ransomware that emerged in early April 2023. This ransomware adds the .boza extension to the encrypted files, making them inaccessible to the user. Like other ransomware variants, Boza Ransomware uses advanced encryption algorithms to lock files, demanding a ransom in exchange for the decryption key. The ransomware targets a wide range of files, including documents, images, videos, audios, and other user data. Once the ransomware infects a computer, it scans the entire system for files and encrypts them using the AES-256 encryption algorithm, making them inaccessible. The ransomware also drops a ransom note called _readme.txt, providing instructions for the user to pay the ransom to the attacker in exchange for the decryption key. The attackers also use a unique encryption key for each infected system, making it difficult for security researchers to develop a universal decryption tool. Below you can see example of the ransom note:

The attackers demand a ransom of several hundred dollars, usually in the form of cryptocurrencies such as Bitcoin, Monero, or Ethereum. In some cases, the attackers also threaten to leak sensitive user data if the ransom is not paid promptly. To be exact, malefactors ask for $980, but offer to reduce the amount to $490 if ransom is paid in 72 hours. To combat this threat, Emsisoft, a renowned cybersecurity firm, has developed a decryption tool that can recover files encrypted by the STOP/Djvu Ransomware variants, including Boza Ransomware. The STOP/Djvu Decryption Tool works by exploiting weaknesses in the ransomware’s encryption method. The tool first identifies the encryption key used by the ransomware to lock the files and then uses this key to decrypt the files. The tool can also recover files encrypted with an offline key, which means the decryption can be performed without the need to connect to the attacker’s command-and-control server. However, for cases encrypted with online keys (98% of all cases) it is almost useless. Boza Ransomware is a dangerous variant of the STOP/Djvu Ransomware that can cause significant damage to user data. To avoid falling victim to this ransomware, users should be cautious when downloading attachments or updates from unknown sources. Additionally, it is recommended to maintain regular backups of important files to mitigate the impact of a ransomware attack. If you become a victim of Boza Ransomware, it is strongly advised not to pay the ransom, as it only encourages the attackers to continue their criminal activities.

How Boza Ransomware infected your computer

Boza Ransomware typically infects computers via malicious email attachments, fake software updates, software cracks, and other social engineering tactics. The attackers often disguise the malware as a legitimate file or software update, tricking users into downloading and executing the malware.

1. Download Boza Ransomware Removal Tool
2. Get decryption tool for .boza 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 Boza Ransomware

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

How to remove Boza Ransomware manually

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

Boza Ransomware files:

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

Boza Ransomware registry keys:

no information

How to decrypt and restore .boza files

Use automated decryptors

Download STOP Djvu Decryptor from EmsiSoft (.boza 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 .boza files, encrypted by Boza 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 .boza 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 Boza 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 .boza 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 .boza

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 Boza 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. Boza 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