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NullByte Virus Remove and Restore _nullbyte Files

nullbyte-ransowmare-wallpaper-sensorstechforumA ransomware virus dubbed NullByte was reported by malware researchers to append the _nullbyte file extension to the files which it encrypts with a strong AES cipher. The name nullbyte originates from the NUL character in ASCII control code, suggesting that an experienced coder may be behind the virus. Further reports indicate the NullByte Ransomware has something to do with two other ransomware variants – DetoxCrypto and Serpico ransomware. The NullByte virus also demands a ransom payoff from the victims of the computers it infects in the size of 0.1 BTC which is approximately 60 US dollars.

Update! There is now a decryptor tool for this ransomware! The tool was created by the malware researcher Michael Gillespie and can be downloaded from the following link, wrapped inside a .zip archive: StupidDecrypter.

Threat Summary

Name NullByte
Type Ransomware
Short Description The ransomware uses AES cipher with an asymmetric algorithm to have a decryption key different than the encryption one.
Symptoms The ransomware will lock all your files with _nullbyte file extension appended to them and put a ransom note in your PC as well as lock it’s screen. The note states that you have to pay the equivalent of 60$ in Bitcoins for decryption.
Distribution Method Spam Emails, Email Attachments, Suspicious Sites
Detection Tool See If Your System Has Been Affected by malware


Malware Removal Tool

User Experience Join Our Forum to Discuss NullByte 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.

NullByte Virus – Distribution

The NullByte ransomware virus may use malvertising campaigns to distribute malicious URLs that may cause an infection when they are visited. Sometimes, potentially unwanted programs that are ad-supported (adware) may also be used to display browser redirects to such URL’s causing direct infection on user PCs.

Another method of distribution of the NullByte Virus has been reported to be massive spam e-mail campaigns that are usually containing e-mail attachments that cause infection via JavaScript or an Exploit Kit attack.

Furthermore, the NullByte virus may also be dropped on the computer via other malware that may currently be residing on it.

NullByte Ransowmare – How Does It Work

NullByte ransomware may drop more than one files upon infection. The files it drops may be executable types of files of the following file formats:

→ .exe, .vbs, .bat, .dll, .cmd, .tmp

After the malicious files have been dropped, the NullByte virus may modify the Windows Registry Editor’s entries with a purpose of running it’s executables on system startup. The targeted registry keys that may be modified are the Run and RunOnce keys located in the following directories:

HKEY_LOCAL_MACHINE\Software\Microsoft\Windows\CurrentVersion\ RunServices

After this has been done, the NullByte ransomware virus may also run an auto executable operation that deletes the shadow volume copies. This may be done via a .bat file that is ran automatically, executing the following vssadmin command as an administrator:

→ vssadmin delete shadows /all /quiet

After the encryption process has started, the NullByte ransomware begins to scan the user’s computer for a wide variety of types of files to encrypt. The virus primarily looks for:

  • Video files.
  • Image files.
  • Files that are associated with widely used programs, like Adobe Photoshop, Adobe Reader, Microsoft Office programs, etc.
  • Database and web server files.
  • Audio files.

As soon as it’s pre-programmed list of file extensions has been put to work, the NullByte ransomware virus begins to encrypt the files. For encryption, it uses the Advanced Encryption Standard. This type of encryption algorithm is believed to be used. After the files have been encoded, the virus then generates a unique decryption key which is then sent to the cyber criminals, by establishing an active connection to their servers.

Files, encrypted by NullByte ransomware can no longer be opened and look like the following:

  • Picture.jpg_nullbyte

The _nullbyte file extension in difference to other expansions is indicated with a “_” symbol instead of “.” which is very distinctive for the _nullbyte virus.

After encryption, the malware performs several other activities that have everything to do with “motivating” it’s victims to pay the ransom money. This includes a wallpaper and another document with a QR code and the following threatening message:

→ “All of your personal files have been encrypted.
The only way you can get your information back is to purchase your decryption key.
The current price is set for 0.1 BTC (USD$57.6) and will be released to you upon successful completion of your transfer to us
Our wallet address is: lHpVz6uSgVjQxzJCeGgwYTbNAaD9tByR4u
and if you are using a BitCoin phone app, you can scan this QR code to transfer us funds.
The more popular BitCoin phone apps include Circle, Coinbase and Airbitz
To find our more information on BitCoins, and what they are, please do a youtube search.
To put in a decryption key request, please use the application called Decrypt Info on your desktop, it is the same application that opened upon completion of filesystem encryption.
We apologize for the invonvinience and will release your decryption key as soon as you transfer funds to our BitCoin Wallet.”

In addition to this, the NullByte virus also displays a lock-screen with the same message and interface that allows users to enter decryption keys that are sent to them after they have paid the ransom of 0.1 BTC.


NullByte Ransomware – Conclusion, Removal and File Restoration

Since this virus originates from two other ransomware viruses – DetoxCrypto and Serpico, it is believed they use the same encryption technique and are developed by the same team. Malware researchers strongly advise against paying any ransom money because specialists may reverse-engineer the NullByte ransomware and come up with a decryptor. Instead, it is strongly advisable to remove this virus using the removal instructions after this article. Not only this, but it is also advisable to use an advanced anti-malware tool to automatically locate all the files associated with Nullbyte ransomware and delete them and detect other malware as well If there is such on your computer.

In addition to this, it is also highly advisable to make sure and try the alternative file restoration methods that are posted after this article in step “3. Restore Files Encrypted by NullByte Ransomware” below.

Ventsislav Krastev

Ventsislav is a cybersecurity expert at SensorsTechForum since 2015. He has been researching, covering, helping victims with the latest malware infections plus testing and reviewing software and the newest tech developments. Having graduated Marketing as well, Ventsislav also has passion for learning new shifts and innovations in cybersecurity that become game changers. After studying Value Chain Management, Network Administration and Computer Administration of System Applications, he found his true calling within the cybersecrurity industry and is a strong believer in the education of every user towards online safety and security.

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Attention! SensorsTechForum strongly recommends that all malware victims should look for assistance only by reputable sources. Many guides out there claim to offer free recovery and decryption for files encrypted by ransomware viruses. Be advised that some of them may only be after your money.

As a site that has been dedicated to providing free removal instructions for ransomware and malware since 2014, SensorsTechForum’s recommendation is to only pay attention to trustworthy sources.

How to recognize trustworthy sources:

  • Always check "About Us" web page.
  • Profile of the content creator.
  • Make sure that real people are behind the site and not fake names and profiles.
  • Verify Facebook, LinkedIn and Twitter personal profiles.


with Anti-Malware
We recommend you to download SpyHunter and run free scan to remove all virus files on your PC. This saves you hours of time and effort compared to doing the removal yourself.
SpyHunter 5 free remover allows you, subject to a 48-hour waiting period, one remediation and removal for results found. Read EULA and Privacy Policy

About the NullByte Research

The content we publish on SensorsTechForum.com, this NullByte how-to removal guide included, is the outcome of extensive research, hard work and our team’s devotion to help you remove the specific malware and restore your encrypted files.

How did we conduct the research on this ransomware?

Our research is based on an independent investigation. We are in contact with independent security researchers, and as such, we receive daily updates on the latest malware and ransomware definitions.

Furthermore, the research behind the NullByte ransomware threat is backed with VirusTotal and the NoMoreRansom project.

To better understand the ransomware threat, please refer to the following articles which provide knowledgeable details.


1. How to Recognize Spam Emails with Ransomware
2. How Does Ransomware Encryption Work?
3. How to Decrypt Ransomware Files
4. Ransomware Getting Greedier and Bigger, Attacks Increase by 40%
5. 1 in 5 Americans Victim of Ransomware

Windows Mac OS X

How to Remove NullByte from Windows.

Step 1: Boot Your PC In Safe Mode to isolate and remove NullByte


Manual Removal Usually Takes Time and You Risk Damaging Your Files If Not Careful!
We Recommend To Scan Your PC with SpyHunter

Keep in mind, that SpyHunter’s scanner is only for malware detection. If SpyHunter detects malware on your PC, you will need to purchase SpyHunter's malware removal tool to remove the malware threats. Read our SpyHunter 5 review. Click on the corresponding links to check SpyHunter's EULA, Privacy Policy and Threat Assessment Criteria

1. Hold Windows Key + R.

2. The "Run" Window will appear. In it, type "msconfig" and click OK.

3. Go to the "Boot" tab. There select "Safe Boot" and then click "Apply" and "OK".

Tip: Make sure to reverse those changes by unticking Safe Boot after that, because your system will always boot in Safe Boot from now on.

4. When prompted, click on "Restart" to go into Safe Mode.

5. You can recognise Safe Mode by the words written on the corners of your screen.

Step 2: Uninstall NullByte and related software from Windows

Here is a method in few easy steps that should be able to uninstall most programs. No matter if you are using Windows 10, 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 are left behind, and that can lead to unstable work of your PC, errors 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:

1. Hold the Windows Logo Button and "R" on your keyboard. A Pop-up window will appear.

2. In the field type in "appwiz.cpl" and press ENTER.

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

Follow the instructions above and you will successfully uninstall most programs.

Step 3: Clean any registries, created by NullByte on your computer.

The usually targeted registries of Windows machines are the following:

  • HKEY_LOCAL_MACHINE\Software\Microsoft\Windows\CurrentVersion\Run
  • HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Run
  • HKEY_LOCAL_MACHINE\Software\Microsoft\Windows\CurrentVersion\RunOnce
  • HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\RunOnce

You can access them by opening the Windows registry editor and deleting any values, created by NullByte there. This can happen by following the steps underneath:

1. Open the Run Window again, type "regedit" and click OK.

2. When you open it, you can freely navigate to the Run and RunOnce keys, whose locations are shown above.

3. You can remove the value of the virus by right-clicking on it and removing it.

Tip: To find a virus-created value, you can right-click on it and click "Modify" to see which file it is set to run. If this is the virus file location, remove the value.

Before starting "Step 4", please boot back into Normal mode, in case you are currently in Safe Mode.
This will enable you to install and use SpyHunter 5 successfully.

Step 4: Scan for NullByte with SpyHunter Anti-Malware Tool

1. Click on the "Download" button to proceed to SpyHunter's download page.

It is 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. Click on the corresponding links to check SpyHunter's EULA, Privacy Policy and Threat Assessment Criteria.

2. After you have installed SpyHunter, wait for it to update automatically.


3. After the update process has finished, click on the 'Malware/PC Scan' tab. A new window will appear. Click on 'Start Scan'.


4. After SpyHunter has finished scanning your PC for any files of the associated threat and found them, you can try to get them removed automatically and permanently by clicking on the 'Next' button.


If any threats have been removed, it is highly recommended to restart your PC.

Video Guide for Automatic and Fast Removal

Step 5 (Optional): Try to Restore Files Encrypted by NullByte.

Ransomware infections and NullByte aim to encrypt your files using an encryption algorithm which may be very difficult to decrypt. This is why we have suggested a data recovery method that may help you go around direct decryption and try to restore your files. Bear in mind that this method may not be 100% effective but may also help you a little or a lot in different situations.

1. Download the recommended Data Recovery software by clicking on the link underneath:

Simply click on the link and on the website menus on the top, choose Data Recovery - Data Recovery Wizard for Windows or Mac (depending on your OS), and then download and run the tool.

Step 6: How to Restore Files Encrypted by Ransomware (Video Guide)

Windows Mac OS X

Get rid of NullByte from Mac OS X.

Step 1: Uninstall NullByte and remove related files and objects

Manual Removal Usually Takes Time and You Risk Damaging Your Files If Not Careful!
We Recommend To Scan Your Mac with SpyHunter for Mac
Keep in mind, that SpyHunter for Mac needs to purchased to remove the malware threats. Click on the corresponding links to check SpyHunter’s EULA and Privacy Policy

1. Hit the ⇧+⌘+U keys to open Utilities. Another way is to click on “Go” and then click “Utilities”, like the image below shows:

2. Find Activity Monitor and double-click it:

3. In the Activity Monitor look for any suspicious processes, belonging or related to NullByte:

Tip: To quit a process completely, choose the “Force Quit” option.

4. Click on the "Go" button again, but this time select Applications. Another way is with the ⇧+⌘+A buttons.

5. In the Applications menu, look for any suspicious app or an app with a name, similar or identical to NullByte. If you find it, right-click on the app and select “Move to Trash


6. Select Accounts, after which click on the Login Items preference.

Your Mac will then show you a list of items that start automatically when you log in. Look for any suspicious apps identical or similar to NullByte. Check the app you want to stop from running automatically and then select on the Minus (“-“) icon to hide it.

7. Remove any left-over files that might be related to this threat manually by following the sub-steps below:

  • Go to Finder.
  • In the search bar type the name of the app that you want to remove.
  • Above the search bar change the two drop down menus to “System Files” and “Are Included” so that you can see all of the files associated with the application you want to remove. Bear in mind that some of the files may not be related to the app so be very careful which files you delete.
  • If all of the files are related, hold the ⌘+A buttons to select them and then drive them to “Trash”.

In case you cannot remove NullByte via Step 1 above:

In case you cannot find the virus files and objects in your Applications or other places we have shown above, you can manually look for them in the Libraries of your Mac. But before doing this, please read the disclaimer below:

Disclaimer! If you are about to tamper with Library files on Mac, be sure to know the name of the virus file, because if you delete the wrong file, it may cause irreversible damage to your MacOS. Continue on your own responsibility!

1: Click on "Go" and Then "Go to Folder" as shown underneath:

2: Type in "/Library/LauchAgents/" and click Ok:

3: Delete all of the virus files that have similar or the same name as NullByte. If you believe there is no such file, do not delete anything.

You can repeat the same procedure with the following other Library directories:

→ ~/Library/LaunchAgents

Tip: ~ is there on purpose, because it leads to more LaunchAgents.

Click the button below below to download SpyHunter for Mac and scan for NullByte:


SpyHunter for Mac

Step 3 (Optional): Try to Restore Files Encrypted by NullByte.

Ransomware infections and NullByte aim to encrypt your files using an encryption algorithm which may be very difficult to decrypt. This is why we have suggested a data recovery method that may help you go around direct decryption and try to restore your files. Bear in mind that this method may not be 100% effective but may also help you a little or a lot in different situations.

1. Download the recommended Data Recovery software by clicking on the link underneath:

Simply click on the link and on the website menus on top, choose Data Recovery - Data Recovery Wizard for Windows or Mac (depending on your OS), and then download and run the tool.

NullByte FAQ

What is NullByte ransomware and how does it work?

NullByte is a ransomware infection - the malicious software that enters your computer silently and blocks either access to the computer itself or encrypt your files.

Many ransomware viruses use sophisticated encryption algorithm how to make your files inaccessible. The goal of ransomware infections is to demand that you pay a ransom payment to get access to your files back.

How does NullByte ransomware infect my computer?

Via several ways.NullByte Ransomware infects computers by being sent via phishing e-mails, containing virus attachment.

This attachment is usually masked as an important document, like an invoice, bank document or even a plane ticket and it looks very convincing to users.

After you download and execute this attachment, a drive-by download occurs and your computer is infected with the ransomware virus.

Another way, you may become a victim of NullByte is if you download a fake installer, crack or patch from a low reputation website or if you click on a virus link. Many users report getting a ransomware infection by downloading torrents.

How to open .NullByte files?

You can't. At this point the .NullByte files are encrypted. You can only open them once they are decrypted.

Decryptor did not decrypt my data. What now?

Do not panic and backup the files. If a decryptor did not decrypt your .NullByte files successfully, then do not despair, because this virus is still new.

One way to restore files, encrypted by NullByte ransomware is to use a decryptor for it. But since it's a new virus, advised that the decryption keys for it may not be out yet and available to the public. We will update this article and keep you posted as soon as this decryptor is released.

How Do I restore ".NullByte" files (Other Methods)?

Yes, sometimes files can be restored. We have suggested several file recovery methods that could work if you want to restore .NullByte files.

These methods are in no way 100% guarantee that you will be able to get your files back. But if you have a backup, your chances of success are much greater.

How do I get rid of NullByte ransomware virus?

The safest way and the most efficient one for the removal of this ransomware infection is the use a professional anti malware software. It will scan for and locate NullByte ransomware and then remove it without causing any additional harm to your important .NullByte files.

Also, keep in mind that viruses like NullByte ransomware also install Trojans and keyloggers that can steal your passwords and accounts. Scanning your computer with an anti-malware software will make sure that all of these virus components are removed and your computer is protected in the future.

What to Do If nothing works?

There is still a lot you can do. If none of the above methods seem to work for you, then try these methods:

  • Try to find a safe computer from where you can can login on your own line accounts like One Drive, iDrive, Google Drive and so on.
  • Try to contact your friends, relatives and other people so that they can check if they have some of your important photos or documents just in case you sent them.
  • Also, check if some of the files that were encrypted it can be re-downloaded from the web.
  • Another clever way to get back some of your files is to find another old computer, a flash drive or even a CD or a DVD where you may have saved your older documents. You might be surprised what will turn up.
  • You can also go to your email account to check if you can send any attachments to other people. Usually what is sent the email is saved on your account and you can re-download it. But most importantly, make sure that this is done from a safe computer and make sure to remove the virus first.

More tips you can find on our forums, where you can also asks any questions about your ransomware problem.

How to Report Ransomware to Authorities?

In case your computer got infected with a ransomware infection, you can report it to the local Police departments. It can help authorities worldwide track and determine the perpetrators behind the virus that has infected your computer. Below, we have prepared a list with government websites, where you can file a report in case you are a victim of a cybercrime:

Cyber-security authorities, responsible for handling ransomware attack reports in different regions all over the world:

Reports may be responded to in different timeframes, depending on your local authorities.

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