Nobu ransomware (Virus Removal Instructions) - Free Guide

What is Nobu ransomware?

Nobu ransomware – malicious program developed for money extortion

Nobu ransomware - a threat that demands money from victims for a decryption tool

Nobu ransomware is a virus that encrypts^[1] all non-system files on a computer that it gets access to and then demands a ransom in cryptocurrency for a decryption tool. This virus derives from a constantly increasing family of Djvu ransomware, which consists of over 260 versions – it is one of the most prominent strains that targets regular computer consumers.

The Nobu virus is almost exclusively spread via software cracks, pirated program installers, and similar files typically placed on torrent or similar sites, so users download the payload themselves. Once instilled on the computer, the malware first alters Windows settings, inserts new modules, and only then proceeds with data encryption.

During this process, ransomware uses RSA^[2] encryption algorithm and appends each file with .nobu extension. Suchlike modified data becomes inaccessible until a necessary decryption tool is used. Unfortunately, the decryptor is only accessible to the attackers, and they are not willing to give it away for free.

When the data is locked and renamed, just like its previous versions like Lisp, Weui, Iiss, and all others, .nobu file virus creates and places text file ransom notes, titled _readme.txt, which claims that victims need to contact the malicious actors via helpmanager@mail.ch or restoremanager@airmail.cc email and pay the ransom of $980/$490 for the decryptor.

The ransom note of Nobu ransomware is long and quite informative, although it doesn't really differ from all other ransom notes of related cryptoviruses. First of all, the cybercriminals explain to the victims that all their files were encrypted and that the only way to regain access to their data is to purchase a decryption tool, aka pay the ransom.

To convince their victims, the attackers suggest sending them one file for free decryption – this suggestion should prove that the ransomware decryptor exists and works as intended. If the free decryption guarantee doesn't persuade the victim to pay the ransom, the criminals add a link to a video where the promised decryption tool can be seen in action.

In other words, the hackers are bending over backward to convince the victims that they will hold their end of the bargain. They promise discounts and claims to have the one and only one existing Nobu ransomware decryption tool. While they might be right about the tool being accessible only to them, there are other options that just might work for you.

The benevolence of the Nobu virus makers doesn't end there. They offer a 50% discount for the ransom amount if their victims act quickly and contact them within 72 hours of the cyberattacks. Then the price would be $490. If the users are not hasty, they would have to lighten their wallets by $980.

At the end of the ransom note, two emails are given to reach out to the cybercriminals – helpmanager@mail.ch and restoremanager@airmail.cc. Also, an appointed personal victim ID is specified, which should be sent went contacting the perpetrators.

Nobu virus can be stopped by a powerful security program, so it is important not to ignore its warnings

As always, we advise against paying the ransom, and suggest that our readers should focus on Nobu ransomware removal instead. Meeting the demands of the criminal's victims just motivates them to increase the number of attacks and finance them to research new, more effective ways to distribute their created ransomware.

Although manual removal is possible, we advise leaving this work to professionals. Remove Nobu virus with a push of a button with any of these two powerful security apps – SpyHunter 5Combo Cleaner or Malwarebytes. If kept updated regularly, they can serve as excellent tools that could prevent future malware attacks.

It is important to note that malware sample was detected under the following names, according to Virus Total:^[3]

• Trojan.MalPack
• Hacktool.Win32.Shellcode.3!c
• Win32:DropperX-gen [Drp]
• Trojan/Win32.Glupteba.R357174
• Trojan.TR/AD.InstaBot.gzfzd
• Gen:Variant.Ransom.Stop.18 (B).

This once again highlights the importance of a robust security application – it can use behavioral analysis to detect danger within certain files with high accuracy. Unfortunately, many users choose to ignore these warnings and end up infecting their computers with the .nobu virus.

Once you've deleted the Nobu file virus from an infected device, it's time to take care of overall system health. Since malware usually modifies system files and settings to help it thrive within the targeted computer, experts^[4] recommend using the FortectIntego system tune-up tool to revert any changes that the virus might have caused.

The message that the ransomware virus makers send to their victims after successful encryption:

Don't worry, you can return all your files!
All your files like pictures, 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:
hxxps://we.tl/t-Dz5odBd07y
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:
helpmanager@mail.ch

Reserve e-mail address to contact us:
restoremanager@airmail.cc

Your personal ID:

Difference between decryptable and non-decryptable .nobu file virus versions

Previously, this Djvu ransomware family was easily decryptable and many victims got their files recovered after attacks and encryption rounds. However, since August 2019 the ransomware creators got their coding techniques updated and managed to rely on more persistent methods, different victim ID formation techniques. Since .nobu is the extension that came out recently, decryption is barely possible.

Nobu ransomware - a virus that makes changes to commonly used files and can also trigger installs of other malware.

Let's explain why and what is the difference. Offline IDs and encryption keys that were previously used by attackers, so researchers managed to obtain one decryption key and recover all the files locked using the same encryption method and the appendix. That worked for a while, but STOPDecrypter is no longer in use for these newest variants like the Nobu virus.

Right now, since the summer of 2019, Djvu creators managed to rely on the RSA algorithm and online ID forming. During such an encryption process the unique ID and decryption key gets chosen. Unfortunately, to recover files affected by the Nobu ransomware, you or the researcher need to get that key and use a tool accordingly.

Even the existing Emsisofts' decrypter works for offline IDs only and only a handful of versions can be decrypted. It shows that the best .nobu file recovery option could be copies of those files stored in backups. You can possibly wait for the new decryption tool or the hacker database leak. That takes time, so our research shows that data backup creation needs more attention.

Possible recovery methods for .Nobu virus affected data

Usually, Djvu family ransomware gets on everyday computer users' devices when they're visiting and downloading something from torrent websites, such as The Pirate Bay, BitTorrent, 1337x, and others. So for your own safety, please don't use these types of file-sharing platforms no matter what to avoid infections like the Nobu virus.

There aren't many choices for data recovery methods after the ransomware attack. If you had backups, then great news! Remove the infection, perform a system tune-up, and restore your data. If you aren't that lucky, then you might want to try our suggestions at the bottom of this article.

Whatever the case might be, be sure to check back with us in the near future as we always update our readers with the latest news on spyware, tech, ransomware, decryption tools, and so much more. We keep various updates on decryption tools and other issues regarding the family of Djvu that the Nobu virus belongs to.

Remove Nobu ransomware from all infected devices with the help of anti-malware software

Having your computer encrypted by the Nobu virus is a total nightmare – especially for those who never encountered such a computer threat before. Virus termination isn't the same as data recovery, but let's take one step at a time.

Contrary to popular belief, you should not proceed with Nobu ransomware removal immediately if you have no backups available. Instead, you should first copy all the most important files onto a separate medium and only then delete the infection from the system. Best results are achieved when a trustworthy anti-malware app is used to do it, such as SpyHunter 5Combo Cleaner or Malwarebytes. In case malware is interfering with these tools, you could access Safe Mode with Networking and perform a full scan from there – we explain how below.

Nobu file virus is a ransomware-type infection that makes files useless.

It is important to note that Djvu variants are known to compromise users' ability to access certain security-related websites, including 2-spyware. Therefore, if you never dealt with Windows “hosts” file before, you should access the following directory and delete it – Windows will recreate it automatically, and you will be able to navigate through the internet freely again:

• C:\Windows\System32\drivers\etc\

Before trying to decrypt or retrieving your files from the backups, users who suffered from the Nobu ransomware virus attack should run a full system scan with a powerful system tune-up tool like FortectIntego to check (and fix) for any system irregularities caused by the attack.