Geek's Advice

MIIS ransomware takes your files hostage, drops _readme.txt ransom notes

MIIS ransomware is a file-encrypting computer virus that comes from STOP/DJVU malware family. Once the victim downloads the payload, the virus launches in a form of several processes and encrypts all files on the target system, adds .miis extensions to their names and leaves _readme.txt notes in every data folder. For example, a file previously called 1.jpg will appear as 1.jpg.miis after the cyberattack. The ransom note contains a brief message from virus’ developers who state that in order to decrypt .miis files, the victim has to listen to their demands and pay a specified sum of money in Bitcoin. According to the attackers, the victim can write to them via two given email addresses: manager@mailtemp.ch or helpmanager@airmail.cc. If the victim manages to reach an agreement with the criminals and transfer the money within 3 days, the decryption costs $490, otherwise – $980.

MIIS ransomware was made to take victim’s files hostage by encrypting them. Cybercriminals target the most valuable files people store on their personal or work computers – be it images, videos, audio files or documents. Therefore, they use complex encryption algorithms to temporarily ‘secure’ files so these could no longer be accessed. During the attack, the virus encrypts the very first 150 KB of each file, enough to make file inaccessible quickly. This, however, enables victims to repair certain file formats using Media_Repair tool as explained here.

The virus is designed to drop _readme.txt note in every file folder, and this note contains a message from the criminals who suggest purchasing MIIS decryption tool from them. According to the note, the price of this tool is $490 if the victim manages to reach out to the virus’ developers and transfer money within 3 days from the initial infection timestamp. Otherwise, the decryption price rises to $980. In addition, the attackers instruct to transfer the money in cryptocurrency such as Bitcoin as they do not accept regular currency. This ensures that the transaction remains untraceable and the criminals’ identity remains undisclosed.

Cybersecurity experts from Geek’s Advice team as well as FBI advise against ransom payments. Here are some reasons why you shouldn’t pay up:

• No matter what cybercriminals promise you, do not believe them. They cannot be trusted and they are not obliged to do their side of the deal as they cannot be traced down in any way. In other words, you may end up wasting your money for nothing and still have your files encrypted.
• Ransomware-type viruses earn millions of US dollars to malevolent actors each year. This is one of the reasons why so many people join this criminal industry. The more money they collect, the bigger the reach and impact of the criminal activities become.
• Paying a ransom might be considered an illegal act in your country.
• Viruses that belong to STOP/DJVU ransomware family such as MIIS virus run AZORULT Trojan on the infected computer. This is a well-known information stealer which can be remotely controlled by the attacker to perform illegal actions on victim’s PC.

Ransomware infection: what happened to your computer?

MIIS ransomware runs several processes after entering victim’s computer. One of these is called winupdate.exe and it is responsible for displaying a fake Windows update prompt during the attack. This is done in order to trick the victim into thinking that a sudden system slowdown is caused by an ongoing Windows operating system update. At the same time, the ransomware starts scanning all system folders and encrypting personal files found in them. Once encrypted, the ransomware also appends a new file extension and leaves a ransom note in the current directory. Next, the ransomware removes Volume Shadow Copies from the computer, ensuring that the victim won’t succeed to restore files using System Restore points. The virus uses the following CMD command to do the damage on VSS:

_{vssadmin.exe Delete Shadows /All /Quiet}

To cause even more stress for the victim, the ransomware modifies Windows HOSTS file to map a list of computer-help related domains to victim’s localhost IP. In simple terms, this alteration tells your computer system to use your localhost IP instead of whichever IP your DNS server resolves to when you try to access specific website through a web browser. As a result, the victim will run into DNS_PROBE_FINISHED_NXDOMAIN error when trying to open one of such websites. In addition, the ransomware saves bowsakkdestx.txt that contains victim’s public encryption key and personal ID and also saves PersonalID.txt file that contains only the victim’s ID.

However, ruining victim’s files and modifying system files doesn’t seem like enough for STOP/DJVU malware operators, so they also drop AZORULT Trojan on the system. This specific piece of malware functions as a Remote Access Trojan (RAT) that can be used to remotely perform various illegal actions on victim’s computer, such as:

• Downloading malware to the computer and running it;
• Stealing Steam, Telegram login credentials;
• Viewing or deleting files on victim’s computer;
• Stealing cryptocurrency wallets;
• Stealing browser cookies, saved passwords, browsing history and more.

Considering the amount of damage done to your computer system, we strongly advise you to remove MIIS ransomware virus from the system as soon as possible. We highly recommend using a robust antivirus for this matter, such as INTEGO Antivirus that has excellent malware detection rate and fair price. In addition, do not forget to scan your PC with RESTORO to repair ransomware damage on Windows OS files.

Ransomware Summary

How ransomware-type threats are distributed

Ransomware-type viruses commonly await in a form of malicious email attachments, illegal torrent downloads or fake cracking tools. In fact, this STOP/DJVU variant, MIIS file virus can be found in many illegal online downloads. Most of the victims infected with this malware report downloading the virus along with software crack, most commonly for popular programs such as Adobe Photoshop, Corel Draw, Cubase or Adobe Illustrator. Additionally, various KMSPico versions are also known to be used as a distribution vector for this ransomware strain. Needless to say, it is clear that ransomware operators are targeting computer users who are trying to bypass software license fees. Moreover, such computer users are willing to ignore their antivirus’ warnings when downloading such files via various peer-to-peer agents.

We strongly recommend you to support legitimate software developers and get programs from confirmed sources only. Otherwise, you risk installing not only ransomware, but various silent malware such as cryptocurrency miners, Trojans or rookits that usually show no signs of existence when you activate them. In such scenario, threats of such kind can operate on your system for months until noticed.

Yet another popular way to distribute crypto-viruses is to compose deceptive emails and distribute them via various spam campaigns. The attackers attach malicious scripts to popular document formats such as PDF, XLS, DOCX or others and name them as invoice/payment_information/important_notice and similar. Typically, they pretend to be representatives of well-known companies and urge the victim to review attached contents and reply as soon as possible. It is important not to rush to do as said and inspect the letter attentively as there might be some red flags revealing true nature of the sender. However, with each day criminals get so creative and more sophisticated as they use identical company logos and even spoof sender’s email to make it look legitimate. For this reason, our general recommendation is to only open emails that you waited for or expected to receive. If you decide to open the attachment, make sure you save it on your computer first and scan with antivirus to confirm that it is secure to open.

We must also warn STOP/DJVU ransomware victims that cybercriminals from other ransomware gangs have been uploading fake MIIS decryption tools on shady websites in order to double-infect victims with other virus’ kinds. One of ransomware families that’s known for using such technique is called ZORAB.

Remove MIIS ransomware virus and decrypt .miis files

Since your computer has been infected with one of the most dangerous virus’ types nowadays, we cannot stress this enough how important it is to secure your computer without any delay. Therefore, we suggest that you scan your computer with an up-to-date antivirus such as INTEGO Antivirus to eliminate malware remains. Then, we also recommend scanning with RESTORO to repair virus damage on Windows OS files. Do not forget to follow detailed steps down below to ensure smooth computer cleanse process.

Once you complete MIIS virus removal procedure, we suggest taking the following actions:

• Register this cybercrime incident to your local authority. You can find some references below the article.
• Use data backups to restore your files in case you have created them prior to the attack.
• Follow the given instructions to decrypt or repair files affected by STOP/DJVU versions.
• Change your passwords for sites saved in your browser. This is recommended due to the fact that Azorult Trojan is capable of stealing them. Do not forget to change Steam, Telegram and Skype passwords as well.

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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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.