Remove .MASTER Ransomware and Restore Files (Update July 2017)

An article created to show you how to remove the .MASTER file virus (BTCWare’s latest variant) and restore files that have been AES encrypted by this virus.

A ransomware infection, known to be the notorious BTCWare ransomware has been released as a new variant of the virus family. Unlike the other BTCWare versions, the .master iteration cannot be decrypted so far and uses an AES encryption algorithm to extort victims whose computers have been infected. The victims have to pay a hefty ransom fee in order to get their files decrypted by the ones behind the .master ransomware infection. In case your computer has been infected by this virus, we advise you to read this article thoroughly.

Threat Summary

Name	.master Ransomware
Type	Ransomware, Cryptovirus
Short Description	Encrypts the files on the infected computer using AES algorithm. Demands ransom payoff in BitCoin. The ransom varies.
Symptoms	The files are encrypted with the .master file extension added to them. The virus drops a ransom note, named !#_RESTORE_FILES_#!.inf.
Distribution Method	Spam Emails, Email Attachments, Executable files
Detection Tool	See If Your System Has Been Affected by .master Ransomware Download Malware Removal Tool
User Experience	Join Our Forum to Discuss .master Ransomware.
Data Recovery Tool	Windows Data Recovery by Stellar Phoenix Notice! This product scans your drive sectors to recover lost files and it may not recover 100% of the encrypted files, but only few of them, depending on the situation and whether or not you have reformatted your drive.

Update July 2017 A new version of BTCWare ransomware has come out into the wild. The virus uses a new malicious file extension, called .aleta which i adds to the encrypted files. Malware eresearchers believe it is spread via malicious spam e-mails carrying documents that contain malicious macros within them. Furthermore, researcher Michael Gillespie notified of a decrypter being released for the .MASTER BTCWare variant. You can now decrypt your files for free if you have saved them.

.master Ransomware Distribution Methods

Since the Master ransomware as many refer to it with this name is a variant of the BTCWareransomware, it may use the same methods to be spread and infect victims. The primary strategy of those methods is to send a massive spam campaign with e-mails that aim for one thing only – to convince unsuspecting users that the situation is critical and they must either click on an e-mail attachment or open a web link that may eventually lead to infection. To do this, Master ransomware may pretend to be a large organization, such as:

• Amazon
• PayPal
• FedEx
• DHL
• eBay
• Other

The messages usually have deceptive content, also known as “social engineering”. They may claim that there is an order awaiting confirmation or any other form invoices or important documents. Then, the user may be misled to click on the malicious e-mail.

BTCWare .master Ransomware – Analysis

After the infection file of the .master ransomware variant is opened, the virus begins to drop it’s payload. This happens by either extracting the payload onto the infected computer or simply connecting to a remote server hosted by the cyber-criminals and download it from there. After this has been done, the malicious files of Master ransomware are then dropped onto the computer of the user and may reside in the following locations:

• %AppData%
• %Roaming%
• %Local%
• %LocalLow%
• %Temp%

Those files include the ransom note of .master ransomware which is named !#RESTORE_FILES_#!.inf. It has the following content:

The .master ransomware virus may begin to modify multiple different Windows processes on the compromised computer system. This is done with the purpose of changing crucial settings on the infected computer, like deleting the backups and shadow volume copies by using the following Windows Command Prompt commands:

→ process call create “cmd.exe /c
vssadmin.exe delete shadows /all /quiet
bcdedit.exe /set {default} recoveryenabled no
bcdedit.exe /set {default} bootstatuspolicy ignoreallfailures

.master Ransomware’s Encryption Process

For the encryption process of the BTCWare .master ransomware variant to succeed, the virus uses a patched AES encryption algorithm. If applied properly, it is very difficult to decrypt the encrypted files by this virus. The files that the .master ransomware looks for to encrypt on infected computers are usually the following:

→ .1c, .3fr, .accdb, .ai, .arw, .bac, .bay, .bmp, .cdr, .cer, .cfg, .config, .cr2, .crt, .crw, .css, .csv, .db, .dbf, .dcr, .der, .dng, .doc, .docm, .docx, .dwg, .dxf, .dxg, .eps, .erf, .gif, .htm, .html, .indd, .iso, .jpe, .jpeg, .jpg, .kdc, .lnk, .mdb, .mdf, .mef, .mk, .mp3, .mp4, .mrw, .nef, .nrw, .odb, .ode, .odm, .odp, .ods, .odt, .orf, .p12, .p7b, .p7c, .pdd, .pdf, .pef, .pem, .pfx, .php, .png, .ppt, .pptm, .pptx, .psd, .pst, .ptx, .r3d, .rar, .raw, .rtf, .rw2, .rwl, .sql, .sr2, .srf, .srw, .tif, .wb2, .wma, .wpd, .wps, .x3f, .xlk, .xls, .xlsb, .xlsm, .xlsx, .zip

After the .master ransomware has already encrypted the files, the virus then displays the files with the .master file extension after their name, for example:

It is believed that the cyber-criminals behind the .master virus have chosen this file extension in particular, because all of the previous variants of BTCWare have already been decrypted using a master decryption key which malware researchers uncovered earlier. And by doing this, the cyber-criminals might aim to mock those researchers.

Remove BTCWare and Restore .master Encrypted Files

Before removing BTCWare .master variant, it is important to backup the encrypted files beforehand.

Then, you can proceed with the removal of the virus. For it to succeed, we advise following the removal instructions underneath. They are specifically designed to help you in isolating the threat and removing all related objects to .master ransomware. In case you lack the experience to remove this virus manually, cybersec experts often advise to use and advanced anti-malware program which will automatically take care of the removal process for you.

In case you are looking for a method to restore your encrypted files, we urge you to do It by trying the alternative method for file recovery below. They are specifically designed to help you recover at least some of the encrypted files. You can find them in step “2. Restore files encrypted by .master Ransomware”.

Manually delete .master Ransomware from Windows and your browser

Note! Substantial notification about the .master Ransomware threat: Manual removal of .master Ransomware requires interference with system files and registries. Thus, it can cause damage to your PC. Even if your computer skills are not at a professional level, don’t worry. You can do the removal yourself just in 5 minutes, using a malware removal tool.

1. Remove or Uninstall .master Ransomware in Windows

Remove or Uninstall .master Ransomware in Windows.

Step 1: Remove/Uninstall .master Ransomware in Windows

Here is a method in few easy steps to remove that program. No matter if you are using Windows 8, 7, Vista or XP, those steps will get the job done. Dragging the program or its folder to the recycle bin can be a very bad decision. If you do that, bits and pieces of the program get left behind, and that can lead to unstable work of your PC, mistakes with the file type associations and other unpleasant activities. The proper way to get a program off your computer is to Uninstall it. To do that:

Hold the Windows Logo Button and “R” on your keyboard. A Pop-up window will appear (fig.1).

In the field type in “appwiz.cpl” and press ENTER (fig.2).

This will open a window with all the programs installed on the PC.
Select the program that you want to remove, and press “Uninstall” (fig.3).

Follow the instructions above and you will successfully uninstall .master Ransomware.

2. Remove .master Ransomware from Your Browser and Your Registry Editor

Remove .master Ransomware from Your Browser.

Remove a toolbar from Mozilla FirefoxRemove a toolbar from Google Chrome Remove a toolbar from Internet Explorer Remove a toolbar from Safari Fix registry entries created by .master Ransomware on your PC.

Start Mozilla Firefox Open the menu window

Select the “Add-ons” icon from the menu

Select .master Ransomware and click “Remove”

After .master Ransomware is removed, restart Mozilla Firefox by closing it from the red “X” in the top right corner and start it again.

Start Google Chrome and Open the drop menu

Move the cursor over “Tools” and then from the extended menu choose “Extensions“

From the opened “Extensions” menu locate .master Ransomware and click on the garbage bin icon on the right of it.

After .master Ransomware is removed, restart Google Chrome by closing it from the red “X” in the top right corner and start it again.

Start Internet Explorer:

Click “‘Tools’ to open the drop menu and select ‘Manage Add-ons’

In the ‘Manage Add-ons’ window, make sure that in the first window ‘Add-on Types’, the drop menu ‘Show’ is on ‘All add-ons’

Select .master Ransomware to remove, and then click ‘Disable’. A pop-up window will appear to inform you that you are about to disable the selected toolbar, and some additional toolbars might be disabled as well. Leave all the boxes checked, and click ‘Disable’.

After .master Ransomware has been removed, restart Internet Explorer by closing it from the red ‘X’ in the top right corner and start it again.

Start Safari

Open the drop menu by clicking on the sprocket icon in the top right corner.

From the drop menu select ‘Preferences’
In the new window select ‘Extensions’
Click once on .master Ransomware
Click ‘Uninstall’

A pop-up window will appear asking for confirmation to uninstall .master Ransomware. Select ‘Uninstall’ again, and the .master Ransomware will be removed.

Some malicious scripts may modify the registry entries of your computer to change different settings. This is why manual clean up of your Windows Registry Database is strongly recommended. Since the tutorial on how to do this is a bit lenghty, we recommend following our instructive article about fixing registry entries.

Automatically remove .master Ransomware by downloading an advanced anti-malware program

1. Remove .master Ransomware with SpyHunter Anti-Malware Tool and back up your data

Remove .master Ransomware with SpyHunter Anti-Malware Tool

1. Install SpyHunter to scan for and remove .master Ransomware.2. Scan with SpyHunter to Detect and Remove .master Ransomware. Back up your data to secure it against infections and file encryption by .master Ransomware in the future.

Step 1:Click on the “Download” button to proceed to SpyHunter’s download page.

Download

Malware Removal Tool

It is highly recommended to run a scan before purchasing the full version of the software to make sure that the current version of the malware can be detected by SpyHunter.

Step 2: Guide yourself by the download instructions provided for each browser.
Step 3: After you have installed SpyHunter, wait for it to automatically update.

Step1: After the update process has finished, click on the ‘Scan Computer Now’ button.

Step2: After SpyHunter has finished scanning your PC for any .master Ransomware files, click on the ‘Fix Threats’ button to remove them automatically and permanently.

Step3: Once the intrusions on your PC have been removed, it is highly recommended to restart it.

Back up your data to secure it against attacks in the future

IMPORTANT! Before reading the Windows backup instructions, we highly recommend to back up your data automatically with cloud backup and insure it against any type of data loss on your device, even the most severe. We recommend reading more about and downloading SOS Online Backup .

SOS Online Backup

2. Restore files encrypted by .master Ransomware

Restore Files Encrypted by .master Ransomware

Ransomware infections like .master Ransomware aim to encrypt your files using an encryption algorithm which may be very difficult to directly decrypt. This is why we have suggested several alternative methods that may help you go around direct decryption and try to restore your files. Bear in mind that they may not be 100% effective but they may help you little or a lot in some situations.

Method 1: Scanning your drive’s sectors by using Data Recovery software.
Another method of restoring your files is by trying to bring back your files via data recovery software. Here are some suggestions for preferred data recovery software solutions:

• Stellar Phoenix Data Recovery Technicians License(Pro version with more features)
• Stellar Phoenix Windows Data Recovery
• Stellar Phoenix Photo Recovery

Method 2: Trying Kaspersky and EmsiSoft’s decryptors.
If the first method does not work, we suggest trying to use decryptors for other ransomware viruses, in case your virus is a variant of them. The two primary developers of decryptors are Kaspersky and EmsiSoft, links to which we have provided below:

• Kaspersky Decryptors
• Emsisoft Decryptors

Urgent! It is strongly advisable to first remove the .master Ransomware threat before attempting any decryption, since it may interfere with system files and registries. You can do the removal yourself just in 5 minutes, using an advanced malware removal tool.

Method 3: Using Shadow Explorer

To restore your data in case you have backup set up, it is important to check for shadow copies in Windows using this software if ransomware has not deleted them:

• Shadow Explorer

Method 4: Finding .master Ransomware decryption key while it communicates it via a network sniffing software.

Another way to decrypt the files is by using a Network Sniffer to get the encryption key, while files are encrypted on your system. A Network Sniffer is a program and/or device monitoring data traveling over a network, such as its internet traffic and internet packets. If you have a sniffer set before the attack happened you might get information about the decryption key. See how-to instructions below:

Instructions on How to Find Decryption Key for Files Encrypted By Ransowmare

Optional: Using Alternative Anti-Malware Tools

Remove .master Ransomware Using Other Alternative Tools

STOPZilla Anti Malware

1. Download and Install STOPZilla Anti-malware to Scan for And Remove .master Ransomware.
Step 1: Download STOPZilla by clicking here.
Step 2: A pop-up window will appear. Click on the ‘Save File’ button. If it does not, click on the Download button and save it afterwards.

Step 3: After you have downloaded the setup, simply open it.
Step 4: The installer should appear. Click on the ‘Next’ button.

Step 5: Check the ‘I accept the agreement’ check circle if not checked if you accept it and click the ‘Next’ button once again.

Step 6: Review and click on the ‘Install’ button.

Step 7: After the installation process has completed click on the ‘Finish’ button.

2. Scan your PC with STOPZilla Anti Malware to remove all .master Ransomware associated files completely.
Step 1: Launch STOPZilla if you haven’t launched it after install.
Step 2: Wait for the software to automatically scan and then click on the ‘Repair Now’ button. If it does not scan automatically, click on the ‘Scan Now’ button.

Step 3: After the removal of all threats and associated objects, you should Restart your PC.

Vencislav Krustev

A network administrator and malware researcher at SensorsTechForum with passion for discovery of new shifts and innovations in cyber security. Strong believer in basic education of every user towards online safety.

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