Nooa Ransomware - How to remove

Nooa is file-locking ransomware that attacks Windows PCs and spreads with pirated and fake programs and files. It might spread together with other malicious programs.

Nooa encrypts files, making them impossible to open. Then asks for money to fix them.

About Nooa ransomware:

Threat type	Ransomware, trojan.
How Nooa infects computers	It spreads on malicious, unreliable pirating sites, it encrypts files and changes their names to end with “.nooa”, it changes antivirus settings, deletes backups, and causes other problems.
How to improve your security	Keep backups of your files separate from your PC, use good antivirus programs to stop infections, use multi-factor authentication to protect your accounts from being hacked.
How to delete Nooa	Remove malware with antivirus programs (Spyhunter, etc.), or reset your PC and delete all the malicious files.

How Nooa ransomware works

Nooa asks for money

Nooa is a dangerous, malicious program. Malicious actors created it to infect people’s computers and extort them.

Once Nooa has infected a computer, corrupts the files it finds on it. It does this by encrypting the files and hiding the decryption password. Without the password, the files are as good as gone.

The people who operate Nooa have the decryption passwords (keys) of the encrypted files. They want money for the keys: from $490 to $980. This is how these criminals make money.

The scheme must be pretty successful as it’s been around for a while. Nooa ransomware is part of an established family of ransomware: Djvu. Djvu is created and maintained by a group of cybercriminals who keep releasing new variants, such as Aeur, Guer, Muuq, Moqs, and others. It’s well known to ransomware experts, but sadly, no easy solution to this malware exists.

Signs that Nooa is on your PC

Here are a few signs that Nooa ransomware attacked your PC:

• files use black page icons,
• file names end with unusual extensions (“.nooa” if your Windows is set to display file type extensions),
• text files called _readme appear in some folders (illustration above),
• some websites don’t open,
• unfamiliar browser extensions might be installed, your browser might behave strangely.

By the time you notice Nooa ransomware on your PC, it’s too late to stop it. You might still want to disconnect your computer from the internet. This way, malware on your computer won’t be able to communicate with malicious actors.

The _readme.txt files that Nooa creates ask for money for fixing the corrupted (encrypted) files. The email addresses in the note ([email protected] and [email protected]) are to contact operators of this malware to figure out paying the ransom.

How to remove Nooa

Can you recover your files?

Before deleting Nooa, decide what you want to do with the corrupted files.

If you have backups of all your files (you might want to check if they’re okay – Nooa does delete local backups), then you only need to delete all the data that Nooa encrypted and restore the backups.

If you don’t have backups, you can keep the Nooa-encrypted files (they’re harmless) somewhere where you won’t accidentally delete or change them.

We have an article on the options that ransomware victims have to recover their data. It discusses file undeletion, repair, and what to watch out for if you decide to pay the ransom.

One thing specific to Djvu (Nooa’s brand of ransomware) is the Emsisoft decryptor. If you scan your files with it, it’ll tell you if your decryption key is unique and, if it’s not, another victim could pay the ransom and get the key to unlock your files, too.

How to delete malware

To use your computer again, it’s important to clean it: remove Nooa ransomware and see if any other malicious programs and files are on it. They must be deleted.

Good antivirus programs (Spyhunter, others) can delete Nooa ransomware. Security tools can also find other malicious files and programs. Nooa malware may mess with antivirus settings and files, so if your antivirus isn’t working properly, you might want to update or reinstall it.

You could reset Windows, but if you choose to keep your files, malware will persist. It’s still worth doing an antivirus scan.

Important -- edit the hosts file to unblock security websites

TL DR : The hosts file is edited to block security sites Before the virus can be removed, it's necessary to fix the hosts file (the file which controls which addresses connect to which IPs). That is the reason the majority of security websites is inaccessible when infected with this particular parasite. This infection edits this file to stop certain websites, including anti-malware download sites, from being accessed from the infected computer, making browsers return the "This site can't be reached" error. Luckily, it's trivial to fix the file and remove the edits that were made to it.

Find and edit the hosts file

The hosts file can be found on C:/Windows/System32/Drivers/etc/hosts. If you don't see it, change the settings to see hidden files.

1. In the Start Menu, search for Control Panel.
2. In the Control Panel, find Appearance and Personalization.
3. Select Folder Options.
4. Open the View tab.
5. Open Advanced settings.
6. Select "Show hidden files...".
7. Select OK.

Open this file with administrator privileges.

1. Open the Start Menu and enter "notepad".
2. When Notepad shows up in the result, right-click on it.
3. In the menu, choose "Run as administrator"
4. File->Open and browse for the hosts file.

The hosts file should look like this: Delete additional lines that they connect various domain names to the wrong IP address. Save the file.

Download and run the antivirus program

After that, download antivirus programs and use them to remove the ransomware, the trojan, and other malware. Spyhunter (https://www.2-viruses.com/reviews/spyhunter/dwnld/).

Automatic Malware removal tools

How to recover Nooa Ransomware encrypted files and remove the virus

Step 1. Restore system into last known good state using system restore

1. Reboot your computer to Safe Mode with Command Prompt:

for Windows 7 / Vista/ XP

• Start → Shutdown → Restart → OK.
• Press F8 key repeatedly until Advanced Boot Options window appears.
• Choose Safe Mode with Command Prompt.

for Windows 8 / 10

• Press Power at Windows login screen. Then press and hold Shift key and click Restart.
• Choose Troubleshoot → Advanced Options → Startup Settings and click Restart.
• When it loads, select Enable Safe Mode with Command Prompt from the list of Startup Settings.

 

2.Restore System files and settings.

• When Command Prompt mode loads, enter cd restore and press Enter.
• Then enter rstrui.exe and press Enter again.
• Click “Next” in the windows that appeared.
• Select one of the Restore Points that are available before Nooa has infiltrated to your system and then click “Next”.
• To start System restore click “Yes”.

 

Step 2. Complete removal of Nooa Ransomware

After restoring your system, it is recommended to scan your computer with an anti-malware program, like Spyhunter and remove all malicious files related to Nooa. You can check other tools here.  

Step 3. Restore Nooa Ransomware affected files using Shadow Volume Copies

If you do not use System Restore option on your operating system, there is a chance to use shadow copy snapshots. They store copies of your files that point of time when the system restore snapshot was created. Usually Nooa tries to delete all possible Shadow Volume Copies, so this methods may not work on all computers. However, it may fail to do so. Shadow Volume Copies are only available with Windows XP Service Pack 2, Windows Vista, Windows 7, and Windows 8. There are two ways to retrieve your files via Shadow Volume Copy. You can do it using native Windows Previous Versions or via Shadow Explorer. a) Native Windows Previous Versions Right-click on an encrypted file and select Properties → Previous versions tab. Now you will see all available copies of that particular file and the time when it was stored in a Shadow Volume Copy. Choose the version of the file you want to retrieve and click Copy if you want to save it to some directory of your own, or Restore if you want to replace existing, encrypted file. If you want to see the content of file first, just click Open.

b) Shadow Explorer It is a program that can be found online for free. You can download either a full or a portable version of Shadow Explorer. Open the program. On the left top corner select the drive where the file you are looking for is a stored. You will see all folders on that drive. To retrieve a whole folder, right-click on it and select “Export”. Then choose where you want it to be stored.

Step 4. Use Data Recovery programs to recover Nooa Ransomware encrypted files

There are several data recovery programs that might recover encrypted files as well. This does not work in all cases but you can try this:

• We suggest using another PC and connect the infected hard drive as slave. It is still possible to do this on infected PC though.
• Download a data recovery program.
• Install and scan for recently deleted files.

Note: In many cases it is impossible to restore data files affected by modern ransomware. Thus I recommend using decent cloud backup software as precaution. We recommend checking out Carbonite, BackBlaze, CrashPlan or Mozy Home.