Geek's Advice

MMNN ransomware is a malicious file-encrypting virus used in cyber attacks

MMNN ransomware, also known as MMNN file virus, is a malicious computer program designed to encrypt all files on victim’s computer. The malware marks them with .mmnn file extensions, which indicates a STOP/DJVU ransomware attack (207th version). The virus leaves _readme.txt ransom notes all over the computer, informing the victim that there are no ways to open encrypted files except paying the ransom. The criminals behind this malicious program demand paying $490-$980 to them, as they are the only ones having the decryption keys. What is also worth your attention is that the virus installs Azorult Trojan on the system, which is capable of stealing your private passwords.

MMNN ransomware attack starts when the computer user downloads a malicious file from the Internet unknowingly. Once it gets access to the computer system, it starts encrypting all files stored on victim’s PC and connected devices. As a consequence, the victim finds a pile of files with old names but new extensions that are impossible to open. This instantly causes a frustration, because the encryption turns all victim’s work files or precious memories into useless data.

The ransom note suggests contacting the attackers via one of the provided emails – helpdatarestore@firemail.cc or helpmanager@mail.ch. The victim must provide his personal ID in the message. If desired, an encrypted file can be attached to the email for free decryption. This way, the criminals seek to prove that the decryption tool exists.

However, please understand that paying the ransom means following the attackers’ demands and supporting their filthy business. The only way to fight these attackers is to regularly create backups and store them on external storage devices, which could prevent absolute data loss in the future. However, you must also not click on malicious links or illegal downloads online if you want to avoid MMNN file virus attack.

Now that you have learned the purpose of the file-encrypting malware, remove MMNN ransomware virus along with AZORULT Trojan immediately. We recommend using a trustworthy anti-malware to remove the virus, but do it in Safe Mode with Networking (as explained in the guide below).

Offline and online encryption keys and decryption explained

Once MMNN ransomware infects a computer, it first checks whether it can connect to its Command&Control server. If the connection succeeds, the malware receives an individual online encryption key, which is used for data corruption. In online encryption case, each victim gets his or her data encrypted with different keys.

However, when the virus fails to connect to C2 server, it uses an offline key, which is the same for all MMNN virus victims. To put it differently, a decryption key for all offline attack victims is also the same. Therefore, once someone pays the ransom for the offline key, all offline key victims can decrypt .mmnn extension files instantly, which cannot be said about the online attack.

You can check whether you’re a “lucky” one and whether you were hit by the offline key in C:/SystemID/PersonalID.txt file. If your key or keys end in t1, it means an offline key was used. See DJVU decryption guide for updates.

Threat Summary

Ransomware distribution in detail

MMNN ransomware virus spreads via malicious online downloads. Some victims report receiving a fake file transfer link, while the majority claim to have downloaded a malicious software crack or keygen tool.

Unfortunately, these tools are made to infringe software developers’ copyrights and provide access to licensed program versions for free. If you have attempted to search for such files, there is no wonder why this STOP/DJVU ransomware version is now on your computer.

If you want to avoid STOP/DJVU malware (such as MMNN, OOSS, BTOS, ROOE, stay away from files that you feel aren’t the safest or the most reliable to download. Illegal downloads are a perfect example when victims look for not-so-secure files themselves and trust them access to their computer system, which results in a complete data loss.

Remove MMNN ransomware virus quickly, yourself

The best way to remove MMNN ransomware virus is to boot your PC in Safe Mode with Networking, then download an antivirus or update the one you already have, and run it to delete all malware from your system. Such removal is explained in detail below.

As soon as MMNN ransomware removal is complete, concentrate on data recovery. You might want to try to look for recent data backups that you have created earlier. If you didn’t have backups and your files were encrypted with online key, there is no hope to access files for free ever again.

OUR GEEKS RECOMMEND

Our team recommends a two-step rescue plan to remove ransomware and other remaining malware from your computer, plus repair caused virus damage to the system:

STEP 1. REMOVE AUTOMATICALLY WITH ROBUST ANTIVIRUS

REMOVE & PROTECT WITH INTEGO

Get INTEGO ANTIVIRUS for Windows to remove ransomware, Trojans, adware and other spyware and malware variants and protect your PC and network drives 24/7.. This VB100-certified security software uses state-of-art technology to provide protection against ransomware, Zero-Day attacks and advanced threats, Intego Web Shield blocks dangerous websites, phishing attacks, malicious downloads and installation of potentially unwanted programs.

Use INTEGO Antivirus to remove detected threats from your computer.

Read full review here.

STEP 2. REPAIR VIRUS DAMAGE TO YOUR COMPUTER

DOWNLOAD RESTORO

RESTORO provides a free scan that helps to identify hardware, security and stability issues and presents a comprehensive report which can help you to locate and fix detected issues manually. It is a great PC repair software to use after you remove malware with professional antivirus. The full version of software will fix detected issues and repair virus damage caused to your Windows OS files automatically.

RESTORO uses AVIRA scanning engine to detect existing spyware and malware. If any are found, the software will eliminate them.

Read full review here.

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Alternative software recommendations

Malwarebytes Anti-Malware

Removing spyware and malware is one step towards cybersecurity. To protect yourself against ever-evolving threats, we strongly recommend purchasing a Premium version of Malwarebytes Anti-Malware, which provides security based on artificial intelligence and machine learning. Includes ransomware protection. See pricing options and protect yourself now.

System Mechanic Ultimate Defense

If you're looking for an all-in-one system maintenance suite that has 7 core components providing powerful real-time protection, on-demand malware removal, system optimization, data recovery, password manager, online privacy protection and secure driver wiping technology. Therefore, due to its wide-range of capabilities, System Mechanic Ultimate Defense deserves Geek's Advice approval. Get it now for 50% off. You may also be interested in its full review.

Disclaimer. This site includes affiliate links. We may earn a small commission by recommending certain products, at no additional cost for you. We only choose quality software and services to recommend.

Norbert Webb

Norbert Webb is the head of Geek’s Advice team. He is the chief editor of the website who controls the quality of content published. The man also loves reading cybersecurity news, testing new software and sharing his insights on them. Norbert says that following his passion for information technology was one of the best decisions he has ever made. “I don’t feel like working while I’m doing something I love.” However, the geek has other interests, such as snowboarding and traveling.