The Yzaq virus, known as a ransomware, is part of the STOP family. This malware family is notorious for its malicious file encryption capabilities. When the Yzaq virus gets into a computer system, it targets various types of files, like documents, videos, photos, and more. It changes the file structure and adds the “.yzaq” extension to each encrypted file, making them unusable without the decryption.
Yzaq Virus Overview
Yzaq
🤔 Yzaq virus can be classified as ransomware that originates from the DJVU/STOP family. Its main target is to cipher your files. After that ransomware virus asks its victims for a ransom payment – ($490 – $980) in Bitcoin.
The Yzaq virus is a type of malware that encrypts your files and makes you pay for their restoration. This malware ciphers various file types. ciphered files are identifiable by a distinct “.yzaq” extension. The affected files become inaccessible and unusable.
Then, the ransomware asks for a file decryption payment in Bitcoin from the victims, that ranges from $490 to $980, depending on the time passed after the attack. Usually, a text file with ransom payment guidances is named as “_readme.txt“.
Yzaq Ransomware works with Salsa20 encryption algorithms to cipher the targeted files. Since Yzaq virus uses such a strong encryption method, it becomes particularly difficult, if not impossible, to pick the decryption key without the assistance of the attackers.
Once Yzaq malware finishes the encryption, it shows a ransom note to the victim, asking for a ransom payment in exchange for the decryption key. The ransom note contains instructions on the ways of making the payment and also often includes threats of system wipeout or ransom amounts surge if the demands are not met within a specified timeframe.
I have made a comprehensive list of potential solutions, advice, and methods to stop the Yzaq malware and decrypt your files. There are situations where it may be possible to restore your files, while sometimes, it may be impossible.
📌 Important Reminder!
It is crucial to say that paying off the bill does not guarantee the successful recovery of your files. The hackers who stand behind the Yzaq virus are not trustworthy. There have been instances where people have paid the ransom, only to be denied by the cybercriminals with the decryption key provision.
Yzaq employs a unique key for every victim, with one exception:
The Yzaq virus is highly similar to other DJVU ransomware samples like Ppvw, Ppvt, Ppvs, and Zput. This virus encrypts a wide range of common file types and appends its distinct “.yzaq” extension to all files. For instance, a file named “1.jpg” would be altered to “1.jpg.yzaq” and “2.png” to “2.png.yzaq“.
After successful encryption, the virus spawns a special text file named “_readme.txt” and places it in every folder containing the encrypted files. It also adds the readme file to the desktop, so the victim will not miss the attack even without opening folders.
The image below provides a visual representation of files with the “yzaq” extension:
Encrypted Files by STOP/DJVU Ransomware
| Name | Yzaq Virus |
| Ransomware family1 | DJVU/STOP2 ransomware |
| Extension | .yzaq |
| Ransomware note | _readme.txt |
| Ransom | From $490 to $980 (in Bitcoins) |
| Contact | [email protected], [email protected] |
| Detection | Trojan:Win32/Gozi.RD!MTB, Backdoor.Agent.RD, Trojan:Win32/Aenjaris.AL!bit |
| Symptoms |
|
| Fix Tool |
To remove possible malware infections, scan your PC:
6-day free trial available. |
This message asking payment is for restore files via decryption key:
_readme.txt (STOP/DJVU Ransomware) – The alarming notification insisting users to pay off the ransom to unlock the encrypted data contains these exasperating cautions.
Yzaq ransomware arrives as a set of operations that are needed to carry out different tasks on a victim’s computer. One of the first ones being launched is winupdate.exe, a sneaky process that shows a false Windows update notification during the attack. Such a trick helps to convince the victim that a sudden system slowdown is caused by a Windows update.
Meanwhile, the ransomware runs another process (which name commonly consists of 4 random characters) which commences scanning the disk for target files and encrypting them. Next, the ransomware removes Volume Shadow Copies from the disk using the following CMD command:
vssadmin.exe Delete Shadows /All /Quiet
Once deleted, it becomes impossible to recover the previous computer state using System Restore Points. The issue is, ransomware operators are getting rid of any built-in Windows methods that could help the victim to restore files for free. In addition, the hackers modify the Windows HOSTS file by adding a list of domains to it and mapping them to the localhost IP. As a result, the victim will face a DNS_PROBE_FINISHED_NXDOMAIN error when trying to access one of the blacklisted websites.
It has come to our attention that ransomware endeavors to block websites that post various how-to guides for computer users. It is evident that by restricting specific domains, the crooks are attempting to prevent the victim from connecting to relevant and helpful ransomware-attack-related information online. Malware also keeps two text files on the victim’s computer that offer attack-related information – the victim’s public key and personal ID. These two files are named bowsakkdestx.txt and PersonalID.txt.
After all these alterations, the malware doesn’t stop. Variants of STOP/DJVU have a tendency to install Vidar password-stealing Trojan on compromised systems. This threat has an extensive list of capabilities, including:
- Infiltrating the victim’s computer with malware and executing it to gain unauthorized access.
- Obtaining unauthorized access to login credentials of Steam, Telegram, and Skype.
- Manipulating and viewing files on the victim’s computer without their knowledge.
- Stealing cryptocurrency wallets from the victim’s system.
- Granting the hackers remote control over the victim’s computer for various malicious activities.
- Extracting sensitive information such as browser cookies, saved passwords, and browsing history.
The encryption algorithm in STOP/Djvu ransomware is AES-256. So, once your data is encrypted with an online decryption key, the chances to get your files back are quite low. Thing is, online key is unique for each victim, and picking it will take exceptionally big amount of time.
Obtaining the online decryption key in any other way is also merely impossible. It is stored on a remote server owned by the criminals who spread the Yzaq 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
How To Remove STOP/Djvu Ransomware?
Video Guide
How To Decrypt .yzaq Files?
How to restore big files?
Try deleting .yzaq extension on a few big files and opening them. This malware has issues with large files encryption. Either the virus read and did not encrypt the file, or it bugged and did not add the filemarker. If your files are very large (2GB+), the latter is most likely. Please, text me in the comments whether this helped you or not.
The newest extensions released around the end of August 2019 after the criminals made changes. This includes Ppvw, Ppvt, Ppvs etc.
As a outcome of the alterations 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.
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Select folders for decryption.
Based on the default configurations, the decryptor will automatically choose the available directories in order to decode the currently accessible drives (the connected ones), including the network drives. You can choose extra locations with the “Add” button.
Decryptors typically propose several options depending on the specific malware family. The existing possible options are shown in the Options tab and can be activated or turned off there. You may discover a detailed list of the currently active Options below.
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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]
There is no corresponding decryption key in the Emsisoft decryptor’s database.
✓ No key for New Variant online ID: [your ID]
Notice: this ID appears to be an online ID, decryption is impossible
Your original files were encrypted with an online key. So no one else has the same encryption/decryption key pair. File recovery is only possible through paying the ransom. 🙁
✓ Result: No key for new variant offline ID: [example ID]
This ID appears be an offline ID. Decryption may be possible in the future.
Malware used an offline key, but files could not be restored (the offline decryption key isn’t available yet). Nonetheless, this message is a good news for you, because it might be possible to restore your files in the future. 🙂
It can take a few weeks or months until the decryption key gets found and uploaded to the decryptor. Please follow updates regarding the decryptable DJVU versions here.
✓ Remote name could not be resolved
This stands for a DNS issues. Consider resetting your HOSTS file to default.
How to Restore .yzaq Files?
In some case ransomware is not doom for your files…
The Yzaq ransomware encryption algorithm is next: it ciphers every file byte-by-byte, then saves a duplicate, erasing (not overriding!) the original file. Hence, the data of the file placement on the physical disk is lost, but the original file is not removed from the disk. The cell, or the sector where this file was kept, can still hold this file, but it is not listed by the file system and can be overwritten by data that has been loaded to this drive after the deletion. Hence, it is possible to recover your files using special software.
Anyway, after realizing it was an online algorithm, it is impossible to retrieve my encrypted files. I also had my backup drive plugged in at the time of the virus, and this was also infected, or so I thought. Every folder within my backup drive had been infected and was encrypted. However, despite losing some important files, I retrieved almost 80% of my 2TB storage.
When I started going through the folders, I noticed the readme.txt ransom note in every folder. I opened some of the folders and found that all files that were not in a subfolder within that folder had been encrypted. However, I found a flaw and glimmer of hope when I went into the subfolders in other folders and found that these files had not been encrypted. Every folder within my c and d drives, including subfolders, had been encrypted, but this was not the case with the backup drive. Having subfolders created within a folder has saved 80% of my data.
As I said, I believe this to be only a small loophole on a backup drive. I’ve since found a further 10 % of my data on another hard drive on a different pc. So my advice is if you use a backup drive, create subfolders. I was lucky, I guess. But I was also unlucky that the virus hit as I was transferring some files from my backup.
Hopefully, this can help some other people in my situation.
Jamie NewlandRecovering your files with PhotoRec
PhotoRec is an free open-source program, which is originally created for data recovery from damaged disks, or for files recovery in case if they are unintentionally deleted. However, with time flow, this program received the ability to recover the files of 400 different file types. Hence, it can be used for file restoration after the Yzaq attack.
First, you need to download this app. It is 100% free, but the developer notifies that there is no warranty that your files will be restored. PhotoRec is distributed in a pack with another tool 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 needed – the program has all the files it need inside of the archive, hence, you can fit it on your USB drive, and help your friends/parents/anyone who has been attacked by Yzaq ransomware.
After the start, you will encounter the screen showing you the entire list of your disk spaces. However, this data is presumably futile, because the required menu is placed a bit higher. Click this tab, then choose the disk which was attacked by ransomware.
After choosing the disk, you need to opt for 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 specify the file formats. This feature is located at the bottom, too. As it was mentioned, PhotoRec can regain the files of about 400 different formats.
Finally, you can start files retrieval by pressing the “Search” button. You will observe the screen where the results of the scan and recovery are shown.
Yzaq files recovery Video Guide.
Frequently Asked Questions
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