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

The Nzer virus, known as a ransomware, is part of the STOP family. This malware family is notorious for malicious file ciphering. When the Nzer virus infects a computer system, it scans the system for files like photos, videos, documents, and more. It alters the file structure and appends the “.nzer” extension to each file, making them unusable without the decryption.

Nzer Virus Overview

Nzer

🤔 Nzer virus can be classified as ransomware that originates from the DJVU/STOP family. Its primary purpose is to cipher your files. After that this ransomware asks to pay the ransom – ($490 – $980) in Bitcoin.

The Nzer virus is a ransomware that encrypts your files and asks for a payment to get them decrypted back. Malware targets different file types, particularly documents, photos, videos and the like. You can notice the files touched by ransomware by the “.nzer” extension. Files affected by this malware become impossible to access and use.

Following the encryption, Nzer virus asks for a payment in Bitcoin from its victims. Depenging on the time since the encryption, the price ranges from $490 to $980. Regardless of the circumstances, malware names the ransom note as “_readme.txt“.

Nzer Ransomware uses Salsa20 encryption algorithms to scramble the contents of the targeted files. Since Nzer virus utilizes such a strong ciphering method, it becomes incredibly difficult, if even possible, to find the decryption key without cooperating with the attackers.

Once Nzer malware finishes the encryption, it shows a ransom note to the user, asking for a ransom payment in exchange for the decryption key. The ransom note provides instructions on the ways of making the payment and also often contains threats of data loss or increased ransom amounts if the ransom is not paid within a specified timeframe.

I have created a comprehensive list of potential solutions, tips, and methods to neutralize the Nzer virus and decrypt and recover your files. There are situations when it may be feasible to restore your files, while sometimes, it may be impossible.

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📌 Important Reminder!

It is crucial to note that paying off the ransom is not a guarantee of the successful files recovery. The rascals behind the Nzer virus are known for their untrustworthiness. There were the cases where people have paid the ransom, only to be denied by the cybercriminals with the decryption key provision.

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

The Nzer virus is highly similar to other DJVU ransomware variants such as Nzoq, Nztt, Wzer, and Wzoq. This virus encrypts a wide range of common file types and appends its distinct “.nzer” extension to all files. For instance, a file named “1.jpg” would be altered to “1.jpg.nzer” and “2.png” to “2.png.nzer“.

After successful encryption, malware 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 victim will not miss the attack even without opening folders.

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

Encrypted Files by STOP/DJVU Ransomware

Name	Nzer Virus
Ransomware family¹	DJVU/STOP² ransomware
Extension	.nzer
Ransomware note	_readme.txt
Ransom	From $490 to $980 (in Bitcoins)
Contact	[email protected], [email protected]
Detection	Win32/Filecoder.Conti.L, Win32:PWSX-gen [Trj], PWS:Win32/Fareit!MTB
Symptoms	Disables Volume Shadow copies, making victim’s attempts to restore data futile; Installs password-stealing Trojan on the system, like Vidar Stealer or RedLine Stealer; Successfully installs a SmokeLoader backdoor for remote access; Updates the HOSTS file with a list of domains to block access to certain security-related sites; Implements encryption to lock most of your files (photos, videos, documents) and adds a particular “.nzer” extension;
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 scary alert demanding users to pay the ransom to unlock the encrypted data contains these exasperating cautions.

Nzer ransomware arrives as a set of tasks that are needed to execute different activities on a victim’s computer. One of the primary ones being launched is winupdate.exe, a sneaky process that displays a fraudulent Windows update prompt during the attack. Such a trick helps to convince the victim that a sudden PC slowdown is caused by a Windows update.

At the same time, the ransomware runs another process (usually named by four random characters) which initiates scanning the disk for target files and ciphering them. Then the ransomware removes Volume Shadow Copies from the system disk through the following CMD command:

vssadmin.exe Delete Shadows /All /Quiet

Once deleted, it becomes nearly impossible to recover the previous computer state using System Restore Points. The problem is, ransomware operators are getting rid of any built-in Windows approaches that could assist the victim to restore files for free. In addition, the hackers modify the Windows HOSTS file by including a list of domains to it and directing them to the localhost IP. As a result, the victim will see a DNS_PROBE_FINISHED_NXDOMAIN error when accessing one of the blocked websites.

We noticed that ransomware attempts to block websites that post various how-to guides for computer users. It is obvious that by restricting specific domains, the malefactors are attempting to hinder the victim from reaching relevant and helpful ransomware-attack-related information online. The virus also saves two text files on the victim’s computer that offer attack-related information – the victim’s public encryption key and personal ID. These two files are named bowsakkdestx.txt and PersonalID.txt.

After all these modifications, 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 large list of capabilities, including:

Gathering sensitive data by running malicious software on the victim’s computer.
Acquiring unauthorized login credentials of Steam, Telegram, and Skype accounts.
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 cryptography algorithm used by DJVU/STOP virus is AES-256. So, if your data got encrypted with an online decryption key, the chances to get your files back are quite low. Thing is, this key is unique for each victim, and picking it will take too much time.

Getting the online key in any other way is also close to impossible. It is stored on a command server controlled by the criminals who promote the Nzer malware. For receiving decrypting code the payment should be $980. To get 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

The _readme.txt document also indicates that the computer user should contact the hackers within 72 hours since the file encryption. On the condition of getting in touch within 72 hours, hackers grant a 50% off. Thus the ransom amount will be minimized down to $490.

Yet, stay away from paying the ransom! I highly recommend that you to avoid contacting these scammers and do not pay. One of the most real working solution to recover the lost data is just using the backups you have, or using Decrypter tool from Emsisoft.

The peculiarity of all such viruses is the application a similar set of actions to generate the unique decryption key. Thus, unless the ransomware is still under the stage of development or exhibits some hard-to-track flaws, manually recovering the ciphered data is a thing you can’t perform. The only solution to prevent the loss of your valuable data is to regularly make backups of your critical files.

Note that even if you do create 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 optional external hard drive storage. Alternatively, you may refer to the help of online (cloud) information storage.

It goes without saying, when you store your backup on your common device, it may be similarly ciphered as well as other data. For this reason, storing the backup on your computer’s disk 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.

Nevertheless, these are the common leaks through which it may be injected into your PC:

Utilizing online free hosting resources to distribute the virus discreetly.
Disguising the virus installer within other apps, particularly utilities offered as freeware or shareware.
Propagation through spam emails containing dubious links leading to the virus installation.
Downloading pirated software from illegal peer-to-peer (P2P) resources, which may include hidden malware.

Instances have been reported when the Nzer virus was disguised as some legitimate tool, for example, the messages demanding to start a browser update or a vastly needed codec for online media playback. This is commonly the way how some online frauds aim to force you into deploying the ransomware manually, by actually making you directly participate in this process.

Surely, the fraudulent update alert will not indicate that you are going to actually install the virus. This process will be disguised under some alert stating that you need to install an urgent security update or some suspicious program whatsoever.

Certainly, the software cracks represent the threat too. Using P2P is illegal and may end up with the injection of severe malware, including the Nzer ransomware.

To sum up, what can you do to evade the injection of the ransomware into your computer? Even though there is no 100% assurance to thwart your PC from getting compromised, there are certain tips I want to give you to prevent the Nzer penetration. You must be cautious while setting up free software today.

Verify you always read what the installer offers aside from the main free program. Stay away from running dubious email attachments. Do not run files from the unknown recipients. Naturally, your current anti-malware program must always be updated.

The malware does not states openly about itself. It will not be mentioned in the list of your available programs. However, it will be masked under some malicious process running consistently in the background, that starts at the moment when you launch your computer.

How To Remove Ransomware?

Video Guide

How To Decrypt .nzer Files?

How to restore big files?

Try removing .nzer extension on a few big files and opening them. This malware has issues with large files encryption. Either the virus read and did not lock the file, or it failed and did not add the filemarker. If you have files that are very large (2GB+), the latter is most likely. Please, let me know in comments if that will work for you.

The newest extensions released around the end of August 2019 after the criminals made changes. This includes Nzoq, Nztt, Wzer etc.

As a consequence of the alterations made by the criminals, STOPDecrypter is no longer assisted. 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.

Select folders for decryption.

Based on the default configurations, the decryptor will automatically choose the reachable directories in order to decrypt the currently accessible drives (the connected ones), including the network drives. Additional (optional) locations can be selected with the help of the “Add” button.

Decryptors typically propose several options depending on the specific malware family. The present possible options are displayed in the Options tab and can be activated or deactivated there. You may find a comprehensive list of the currently active Options below.

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]

Emsisoft does not have a corresponding key in the 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. Your key is unique and is kept on the command server, controlled by criminals. File recovery without paying the ransom 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.

Malware used an offline key, though the file recovery operation failed (the offline decryption key isn’t available yet). Nonetheless, receiving this message is good news for you, since 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. Try resetting your HOSTS file to default.

How to Restore .nzer Files?

In some case ransomware is not doom for your files…

The Nzer ransomware encryption mechanism algoritm is next: it encodes every file byte-by-byte, then saves a file copy, 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 absent in the file system and can be overwritten by data that has been loaded to this disk after the removal. Hence, it is possible to restore your files using special software.

I recently had my pc infected by the this virus. It managed to bypass 2 Antivirus software and 2 malware fighters.

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 Newland

Some pointers for recovery repair of Nzer files (true for all STOP/DJVU variants):

I have seen Stop/Djvu variants fail to encrypt deeper nested folders, so that you can check that. You may find those are not encrypted.

This ransomware saves encrypted data to a new file, deletes the original. So there’s a slight chance part of that deleted file can be recovered using file recovery software. It’s unlikely the folder structure can be restored, so a free tool like PhotoRec may be as good as any.

This ransomware only partially encrypts (about the first 150 KB), so depending on file size and type of data, the not encrypted part may be recoverable.

Joep

Recovering your files with PhotoRec

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

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

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

After the start, you will see the screen showing you the complete list of your drives. However, this data is probably irrelevand, because the required menu is placed a bit higher. Click this menu, then choose the disk which was attacked by ransomware.

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

Then, you need to designate 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 start files recovery by pressing the “Search” button. You will view the screen where the findings of the scan and recovery are shown.

Nzer files recovery Video Guide.

Frequently Asked Questions

🤔 How can I open “.nzer” files?

No way. These files are encrypted by ransomware. The contents of encrypted files are not available until they are decrypted.

🤔 Encrypted files contain important information. How can I decrypt them urgently?

If your data remained in the .nzer files are very valuable, then most likely you made a backup copy. If not, then you can try to restore them through the system function – Restore Point. All other methods will require patience.

🤔 You have advised using GridinSoft Anti-Malware to remove Nzer. Does this mean that the program will delete my encrypted files?

Of course not. Your encrypted files do not pose a threat to the computer. What happened has already happened.

🤔 This virus has blocked infected PC: I can’t get the activation code.

In this situation, you need to prepare the memory stick with a pre-installed

🤔 Decryptor did not decrypt all my files, or not all of them were decrypted. What should I do?

Have patience. You are infected with the new version of STOP/DJVU ransomware, and decryption keys have not yet been released. Follow the news on our website. We will keep you posted on when new keys or new decryption programs appear.

🤔 What can I do right now?

The Nzer ransomware encrypts only the first 150KB of files. So MP3 files are rather large, some media players (Winamp for example) may be able to play the files, but – the first 3-5 seconds (the encrypted portion) will be missing. You can try to find a copy of an original file that was encrypted: Files you downloaded from the Internet that were encrypted and you can download again to get the original.