Moka ransomware is another variant from STOP family of malware and as always, it just adapted everything from its predecessors. Nothing new on this edition except that appended file extension on encrypted files, which is obviously .moka.
The spread campaign that is known effective in deploying Moka ransomware is through spam emails, malicious advertisements, software piracy, and links that points to aggressive web pages. Of all the mentioned techniques, Moka ransomware developer’s finds high success rate in infecting the computer by mass-mailing the virus to random email recipients. In this scheme, the malicious code is attached to email while pretending as valuable document file and hackers designed it not to look like an executable type. But once user opens it, it initiates the first stage of the attack where it will drop a number of malicious files on the computer.
Following the preliminary assault is the decryption of user’s files where Moka ransomware specifically selects file types as documents, spreadsheet, movies, images, photos, videos, archives, drawings, databases and similar files that are valuable to victims. Moka ransomware will apply a sophisticated algorithm during the encryption process that will make the data unreadable. Apart from the complex cipher method, all infected files will be appended with .moka extension. As a result, resume.doc will transform into resume.doc.moka after the encryption process.
Same with most STOP member like Shariz, Peta, and Gero, Moka ransomware similarly informs victims about the occurring infection by leaving a ransom note on the same location as .moka files. Here is an excerpt from the said document:
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.
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.
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.
How to Remove Moka Ransomware
Ransomware files are placed deeply into the system and on various locations, thus, thorough scanning is vital to totally remove Moka virus. Aside from our suggested tool, you may also run your own security program.
Though affected files may be impossible to decrypt due to complexity of the encryption, you can still try recovery method like alternative tool, Shadow Explorer or Previous Version as described below.
Stage 1: Scan the Computer with Anti-Malware Tool
1. Download free anti-malware scanner called MalwareBytes Anti-Malware.
Malwarebytes Anti-Malware Download Link (this will open a new window)
2. After downloading, install the program. It may run automatically or you have to double-click on the downloaded file MB3-Setup-[version].exe.
3. Carry out the installation with default setup process.
4. At the last stage of installation process, click the Finish button. The program should launch momentarily.
5. On Malwarebytes Anti-Malware console, select Scan from the menu to see available Scan Method.
6. Next, click on Threat Scan. This is the most complete scan method that will surely find any hidden malicious objects associated to Moka ransomware.
7. Finally, click on Start Scan begin checking the computer for malware and similar threats.
8. Once the scan has completed, the tool will display the list of detected threats. Remove all identified malicious items and restart the computer if necessary.
Stage 2: Double-check for Moka’s leftover with Microsoft’s Malicious Software Removal Tool
1. Download the free scanner called Malicious Software Removal Tool.
Malicious Software Removal Tool Download Link (this will open a new window)
2. The tool automatically checks the operating system and suggest appropriate download version. Click on Download button to begin. Save the file to a convenient location, preferably on Desktop.
3. After downloading the file, Windows will prompt that download has completed. Click Run to start scanning for Moka ransomware. Another option is to browse the location folder and double click on the file to run.
4. The tool will display Welcome screen, click Next. Please note the message “This tool is not a replacement for an antivirus product.” You must understand that this program is made specifically to find and remove malware, viruses, Trojans, and other harmful elements on the computer. It was not designed to protect the computer.
5. Next, you will see Scan Type. Please choose Full Scan to ensure that all Moka ransom virus entities and other harmful files left on the computer will be found and removed. For advanced computer user, you can opt for Customized Scan, if there are other drives or folders you wanted to include in this scan.
6. Full scan may take a while, please wait for Malicious Software Removal Tool to complete the tasks. However, you may cancel the scan anytime by clicking on the Cancel button.
7. After scanning, the tool will reveal all identified threats. There may be other threats that our first scan fails to detect. Please remove/delete all detected items.
8. When removal procedure is complete, you may now close Malicious Software Removal Tool. We hope that Moka ransomware have been completely deleted from the computer. Please restart Windows to proceed with the normal operation.
Stage 3 : Unlocking files with Moka Decryption Tool
Emsisoft Decryptor for STOP Djvu will work only if affected files were encrypted using Offline Keys. Moka ransomware uses the alternate Offline Keys during encryption if there is a problem encountered while communicating to a remote command-and-control server. Follow the guide to start recovering .moka encrypted files.
1. As precautionary measures, we suggest to BACKUP all your .moka encrypted files first on a separate media (USB Drive, Flash Drive, DVD Discs, etc…).
2. Download Emsisoft Decryptor for STOP Djvu from this archive page.
3. Right-click on decrypt_STOPDjvu.exe and click “Run as Administrator“. Windows may prompt “Do you want to allow this app…” just click Yes to continue.
4. By default, the tool will pre-populate the locations where encrypted files were identified. To include other directories, simply click Add Folder button.
5. To start recovering files infected by Moka ransomware, click on Decrypt button to start the procedure. The interface will display status of the current decryption process.
We will update this section once the full decryption tool is on hand. In the meantime, please try other options below if the above procedure is not not effective.
Option 1: Windows Previous Version Tool
Windows Vista and Windows 7 have a feature called Previous Versions. However, this tool is only usable if restore point was made prior to Moka ransomware infection. To use this tool and recover files affected by the virus, please follow these steps:
1. Open My Computer or Windows Explorer.
2. Right-click on the affected files or folders. From the drop-down list, please click on Restore previous versions.
3. New window will open display all backup copy of files and folders you wanted to recover. Choose the appropriate file and click on Open, Copy, or Restore. Restoring selected files overwrites the current encrypted files on the computer.
Option 2: Use ShadowExplorer to restore files encrypted by Moka Ransomware
Just like Previous Version tool, ShadowExplorer is taking advantage of shadow copy created by Windows. This tool allows you to retrieve older version of files before it was encrypted by Moka ransomware.
1. Download ShadowExplorer from the official web site.
2. Install the program with the default settings.
3. The program should run automatically after installation. If not, double-click on ShadowExplorer icon.
4. You can see the drop-down list on top of the console. Please select proper drive and the most recent point-in-time shadow copies of files you wish to restore prior to Moka ransomware infection.
5. Right-click on the Drive, Folder, or File you wish to restore and click Export…
6. Lastly, ShadowExplorer will prompt for location where you want to save the copy of recovered files.