JASA Virus (.JASA File) 🔐 Decrypt & Removal Guide

Jasa virus is categorized as a ransomware strain associated with the STOP/DJVU family. Its primary purpose is to encrypt user files and demand a ransom. When the Jasa virus infects a system, it scans for a variety of file formats, particularly focusing on videos, photos, documents, or so. Subsequently, it employs a robust encryption algorithm to cipher these files, appending the .jasa extension to the compromised files.

Jasa Virus Overview

The Jasa ransomware is a malicious program that encrypts your files and forces you to pay for their recovery. This malware ciphers a wide selection of file types. Ciphered files are identifiable by a distinct “.jasa” extension. As a result, the affected files become impossible to access and use.

After that, the ransomware demands a ransom payment in Bitcoin from the victims, ranging from $490 to $980. Typically, a text file with ransom payment guidances is named as “_readme.txt“.

Jasa Ransomware uses Salsa20 encryption algorithms to scramble the contents of the targeted files. Since Jasa virus employs such a robust ciphering method, it becomes quite hard, if even possible, to pick the decryption key without the assistance of the attackers.

Once Jasa malware finishes the encryption, it shows a ransom note to the user, demanding a ransom payment in exchange for the decryption key. The ransom note provides instructions on how to pay off the bill and also often includes threats of permanent data loss or ransom amounts surge if the ransom is not paid within a specified timeframe.

I have made a comprehensive list of potential solutions, advice, and methods to stop the Jasa malware and decrypt and recover your files. In some cases, you can decrypt the files, while sometimes, it may be impossible.

Jasa uses a unique key for each victim, with one exception:

The Jasa virus is similar to other DJVU ransomware variants like Jaoy, Taqw, Tasa, and Taoy. This virus encrypts a wide range of common file types and appends its distinct “.jasa” extension to all files. For instance, a file named “1.jpg” would be altered to “1.jpg.jasa” and “2.png” to “2.png.jasa“.

Upon successful encryption, the virus spawns a special text file named “_readme.txt” and places it in every folder containing the encrypted files. It as well adds the readme file to the desktop, so the user will not miss its appearance even without opening folders.

The image below provides a visual representation of files with the “jasa” extension:

Encrypted Files by STOP/DJVU Ransomware

This message asking payment is for restore files via decryption key:

_readme.txt (STOP/DJVU Ransomware) – The frightening notification requesting users to pay off the ransom to unlock the encrypted data contains these exasperating admonitions.

The Jasa ransomware arrives on a victim’s computer as a set of tasks intended to carry out specific actions. One of the initial tasks it launches is winupdate.exe, which presents a fake Windows update alert during the attack. This action aims to convince the victim that a sudden PC slowdown occurs due to a Windows update.

Concurrently, the ransomware initiates another process (named with 4 random characters) that scans the PC for target files and encrypts them. Subsequently, the ransomware eliminates Volume Shadow Copies from the system disk using the following CMD command:

vssadmin.exe Delete Shadows /All /Quiet

Once deleted, restoring the previous computer state through System Restore Points becomes virtually impossible. The concern lies in the fact that ransomware operators are eliminating any built-in Windows methods that could assist victims in file recovery without payment. Additionally, the perpetrators modify the Windows HOSTS file by appending a list of domains and mapping them to the localhost IP. Consequently, when attempting to access one of the blocked websites, the victim encounters a DNS_PROBE_FINISHED_NXDOMAIN error.

We have noticed that the ransomware attempts to restrict websites that provide various how-to guides for computer users. Evidently, by limiting access to specific domains, the culprits aim to hinder victims from reaching relevant and helpful information about ransomware attacks online. The malware also deposits two .txt files on the victim’s computer containing attack-related details: the victim’s public key and personal ID. These files are named bowsakkdestx.txt and PersonalID.txt.

After all these alterations, the malware doesn’t cease. Variants of STOP/DJVU tend to deploy Vidar password-stealing Trojan on compromised systems. This threat carries an extensive list of capabilities, including:

• Manipulating and viewing files on the victim’s computer without their knowledge.
• Extracting sensitive information such as browser cookies, saved passwords, and browsing history.
• Obtaining unauthorized access to login credentials of Steam, Telegram, and Skype.
• Granting the hackers remote control over the victim’s computer for various malicious activities.
• Stealing cryptocurrency wallets from the victim’s system.
• Gathering sensitive data by running malicious software on the victim’s computer.

The cryptography algorithm in STOP/Djvu ransomware is AES-256. So, once your data is encrypted with an online decryption key, the possibility to get your files back without paying the ransom are quite low. Thing is, online key is unique for each victim, and picking it will take too much time.

Obtaining the online decryption key in another way is also merely impossible. It is kept on a server controlled by the hackers who spread the Jasa infection. For receiving unlocking key the payment should be $980. To see the payment details, the victims should contact the fraudsters by email ([email protected]).

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 the ransom!

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

_readme.txt file also states that the system user should contact the hackers within 72 hours starting from the moment of files were encrypted. On the condition of getting in touch within 72 hours, hackers grant a 50% off. This decreases the ransom sum down to $490.

Yet, stay away from paying the ransom! I highly recommend that you to avoid contacting these frauds and do not pay. An efficient solution to retrieve the lost data is just using the available backups, or using Decrypter tool from Emsisoft.

The distinctiveness of such malware is the application a similar set of actions for generating the unique decryption key to recover the ciphered data. Thus, unless the ransomware is still in development or exhibits some hard-to-track encryption, manually recovering the ciphered data is a thing you can’t perform. The exclusive resolution to prevent the loss of your valuable data is to regularly make backups of your important files.

Keep in mind that even if you do preserve such backups regularly, they must be kept into a specific location without loitering, not being connected to your main workstation. For instance, the backup may be kept on the USB flash drive or some substitute external hard drive storage. Optionally, you may turn to the help of online (cloud) information storage.

It goes without saying, when you keep your backup data on your regular device, it may be similarly ciphered as well as other data. For this reason, storing the backup on your main computer is surely not a wise idea.

How I was infected?

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

Ransomware attack following a successful phishing attempt.

How To Remove Ransomware?

Video Guide

How To Decrypt .jasa Files?

The newest extensions released around the end of August 2019 after the criminals made changes. This includes Jaoy, Taqw, Tasa etc.

As a result of the changes made by the criminals, STOPDecrypter is no longer backed. It has been replaced with the Emsisoft Decryptor for STOP Djvu Ransomware developed by Emsisoft.

You can download free decryption tool here: Decryptor for STOP Djvu.

1. Select folders for decryption.

   Based on the default configurations, the decryptor will by default choose the available directories in order to unlock the currently reachable drives (the connected ones), including the network drives. You can choose extra locations with the “Add” button.

   Decryptors usually offer several options depending on the specific malware family. The present possible options are presented in the Options tab and can be turned on or disabled there. You may locate a detailed list of the currently active Options below.

2. Click on the “Decrypt” button.

   As soon as you add all the desired locations for decryption into the list, click on the “Decrypt” button in order to initiate the decryption procedure.

   Note that the main screen may turn you to a status view, letting you know of the active process and the decryption statistics of your data:

   

   The decryptor will notify you as soon as the decryption procedure is completed. If you need the report for your personal papers, you can save it by choosing the “Save log” button. Note that it is also possible to copy it directly to your clipboard and to paste it into emails or messages here if you need to do so.

The Emsisoft Decryptor might display different messages after a failed attempt to restore your files:

✓ Error: Unable to decrypt file with ID: [your ID]

✓ No key for New Variant online ID: [your ID]

Notice: this ID appears to be an online ID, decryption is impossible

✓ Result: No key for new variant offline ID: [example ID]

This ID appears be an offline ID. Decryption may be possible in the future.

✓ Remote name could not be resolved

How to Restore .jasa Files?

In some case ransomware is not doom for your files…

The Jasa ransomware encryption mechanism algoritm is next: it ciphers every file byte-by-byte, then saves a duplicate, removing (not overriding!) the original file. Hence, the data of the file placement on the disk drive is lost, but the original file is not erased from the physical disk. The cell, or the sector where this file was stored, can still contain this file, but it is absent in the file system and can be rewritten by data that has been loaded to this drive after the removal. Hence, it is possible to restore your files using special software.

Recovering your files with PhotoRec

PhotoRec is an free open-source program, which is originally created for data recovery from damaged disks, or for data recovery in case if they are unintentionally deleted. However, as time has gone by, this program got the ability to restore the files of 400 different file types. Hence, it can be used for file recovery after the Jasa attack.

First, you need to download this app. It is 100% free, but the developer states that there is no warranty that your files will be recovered. PhotoRec is distributed together with other utility of the same developer – TestDisk. The program archive will bear TestDisk name, but don’t worry. PhotoRec files are right inside.

To launch PhotoRec, you need to find and open “qphotorec_win.exe” file. No setup is required – this program has all the files it need within the archive, hence, you can mount it on your USB drive, and help your friends/parents/anyone who has been attacked by Jasa ransomware.

Upon the start, you will see the screen showing you the full list of your disk spaces. However, this information is probably useless, because the required menu is placed a bit higher. Click this bar, then choose the disk which was attacked by ransomware.

After selecting the disk, you need to pick the destination folder for the recovered files. This menu is located at the lower part of the PhotoRec window. The best decision is to export them on USB drive or any other type of removable disk.

Then, you need to indicate the file formats. This option is located at the bottom, too. As it was mentioned, PhotoRec can retrieve the files of about 400 different formats.

Finally, you can initiate files retrieval by pressing the “Search” button. You will see the screen where the findings of the scan and recovery are shown.

Jasa files recovery Video Guide.

Frequently Asked Questions

1. My files are encrypted by ransomware, what should I do now?
2. About DJVU (STOP) Ransomware.

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