Geek's Advice

FGUI ransomware encrypts all files on a computer, demands ransom

FGUI ransomware is a new computer virus that is associated with the infamous STOP/DJVU ransomware family. After being run on victim’s computer, it encrypts all data stored on it and connected drives. During the cyber attack, this virus marks each file with .fgui extension and drops a ransom-demanding note called _readme.txt in every folder. For example, a file originally named 1.jpg becomes 1.jpg.fgui, document.docx becomes document.docx.fgui and so on. The message left in the ransom note suggests that encrypted files can only be opened with FGUI decryption tool, but in order to access it, the victim is asked to pay a ransom for cybercriminals.

In the ransom note, the cybercriminals ephasize that all files on the computer are encrypted with “strongest” algorithms and that there is no way to open them unless the victim pays a ransom to the attackers. According to them, the data decryption price, or, in other words, the ransom price depends on how quickly the victim contacts the attackers via email addresses included in the _readme.txt file – support@sysmail.ch and helprestoremanager@airmail.cc. If the victim writes within 72 hours/3 days, the crooks set the decryption price to $490. Otherwise, they will demand $980.

When contacted via email, FGUI ransomware operators suggest that the only way to make the transaction to them is via cryptocurrency. For this, they suggest purchasing Bitcoins according to their instructions and sending the amount to their virtual wallet address. The reason why they only accept this form of payment is to avoid being tracked down and arrested. Additionally, they promise to decrypt one small encrypted file for free to prove that they are capable of restoring all data.

At this point, our team of experts would like to remind you that paying a ransom is NOT A RECOMMENDED OPTION. According to FBI suggestions regarding ransom payments, this doesn’t guarantee data recovery and only helps to fund filthy operations organized by cybercriminals. Moreover, you should know that this malignant software tends to carry VIDAR or AZORULT Trojans alongside them only to steal various sensitive data from your computer. These Trojans are capable of grabbing your login credentials (browser-saved passwords, login details for various software such as Steam or Skype, and more), viewing, deleting or dropping additional files to your PC, stealing browsing history, cookies and even more.

If your computer was compromised by this notorious malware, we recommend you to clean up the infection using professional antivirus software while in Safe Mode with Networking. You can find a complete guide how to do it below this article. If you haven’t decided on which antivirus solution to trust, our team recommends INTEGO Antivirus (you can read its review here). Additionally, you may also want to download RESTORO to scan and identify virus damage to Windows OS files. The tool is capable of repairing it without the need to reinstall Windows.

Ransomware Summary

REMOVE MALWARE & REPAIR VIRUS DAMAGE

How ransomware-type threats are distributed

When it comes to ransomware-type threats like FGUI virus, the actors behind them tend to rely on several distribution methods. The most common technique used to spread STOP/DJVU ransomware versions is malicious pirated software versions. These can be downloaded via torrents or directly from dubious websites offering password-secured archived files. The cybercriminals prey on computer users who seek to activate premium software versions without paying for the legitimate license key. According to our research, the criminals tend to use these popular software names when luring the potential victims:

• VMware Workstation;
• AutoCad;
• Corel Draw;
• Tenorshare 4ukey;
• Fifa 20;
• Opera browser;
• Adobe Photoshop;
• Cubase;
• Adobe Illustrator;
• Internet Download Manager;
• League of Legends;
• Virtual DJ Pro;
• KMSPico (illegal Windows activation tool);
• Various AV software.

If you tend to use pirated software versions, remember that by doing so, you risk being fined for copyright infringement. On top of that, you can contaminate your computer with various malware. Even if you do not notice anything suspicious after launching the setup, your computer might already be infected with information-stealing, cryptocurrency-mining or data-encrypting malware. Some of these computer viruses are designed to launch after a computer re-boot, or after a set time period.

We encourage you to avoid downloading illegal software versions and instead support legitimate software developers by purchasing software keys from their official websites or their partners’ sites. At the end of the day, legitimate software licenses cost way less than the amount of money greedy cybercriminals will demand from you after causing damage to your files and private information.

Another way that cybercriminals spread ransomware-type viruses involves malicious email spam. The crooks send malicious files as email attachments, while the email message usually urges the target to open attachments and reply to the sender. The sender typically pretends to be someone they’re not, for instance, a legitimate company representative or target’s colleague or boss. Opening the attachment leads to a severe computer infection. Nowadays, it can be tricky to spot malicious emails, especially when the crooks use email spoofing techniques to hide the real sender’s email address. However, you should look out for tell-tale signs such as typo mistakes, unfamiliar greeting line, weirdly aligned logos or suspicious-looking attachment name and file type.

Finally, computer users who are already affected by ransomware should be careful when looking for data decryption tools online. Usually, when it comes to complex malware variants such as STOP/DJVU, data decryption can be impossible, however some victims do not accept this fact and continue to search and download suspicious tools. This can lead to double-file encryption since cybercriminals prey for victims by uploading fake decryption tools online. You can find trustworthy information about the only possible data repair/decryption solutions for STOP/DJVU in this article. At the moment, only Emsisoft and DiskTuna offer such solutions.

More details about this ransomware attack

This article section summarizes key points of FGUI ransomware modus operandi. The attack begins when the main executable of the ransomware gets launched; this file is usually named with 4 random characters. For example, it might appear as F6B8.exe or 1K9M.exe in the Task Manager. It then downloads several helper processes named as build.exe and build2.exe as well as fake Windows update prompt launcher, winupdate.exe.

The first thing this malware does is figuring out the infected computer’s geolocation. It appears that this ransomware has a whitelist of countries to exclude from data encryption; these countries are Russia, Syria, Uzbekistan, Armenia, Tajikistan, Kyrgyzstan, Ukraine, Kazachstan, and Belarus. To find out the computer’s location, the ransomware connects to https[:]//api.2ip.ua/geo.json and saves the response to a geo.json file. This file contains computer’s IP address, region, country, city, zip code and other details. You can see two examples of such file down below.

The virus also collects other details about the infected computer, including infection timestamp, user name, computer name, keyboard language, hardware details, installed software and active processes lists. Gathered information will be saved to another text file named as information.txt; an example of it is shown below.

In case the ransomware infects a computer that’s located in one of the whitelisted countries, it will delete itself. Otherwise, it proceeds to prepare for the actual data encryption procedure. For this, it connects to its Command&Control server and requests a unique encryption key along with victim’s personal ID. If this connection fails, it switches to offline encryption mode instead.

The good news is that victims affected by offline encryption can hope to decrypt .fgui files in the future. A sign of offline encryption is appearance of t1 characters at the end of the Personal ID string which is located at C:\SystemID\PersonalID.txt. The ransomware also saves the encryption key and ID to another file called bowsakkdestx.txt. You can see examples of both files in the image presented below.

The ransomware now proceeds to encrypt all files on the computer and mark them with additional .fgui extension. The encryption type used is Salsa20+RSA-2048. A screenshot of infected data folder is displayed below.

During the attack, this computer virus drops a copy of _readme.txt note. Contents of it are shown in the image below.

Finally, the ransomware runs a command to delete Volume Shadow Copies using Command Prompt:

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

The last modification is changing Windows HOSTS file. The virus adds a list of domains to restrict on the computer by mapping them to localhost IP. Consequently, the user might run into errors similar to DNS_PROBE_FINISHED_NXDOMAIN when trying to access various ransomware incident response information online.

Remove FGUI Ransomware Virus and Decrypt Your Files

Victims of this ransomware attack are advised to remove FGUI ransomware virus from their computers as soon as possible. The easiest way to do this is to boot your PC in Safe Mode with Networking and then run a reliable AV solution such as INTEGO Antivirus, which is highly recommended by our team. Further recommendations include:

• Report cybercrime incident to your local police department.
• After deleting malware from your PC, use data backups to restore as many files as possible.
• Read more about decryption of STOP/DJVU affected data.
• Change login credentials for all accounts used on the compromised computer.
• Download RESTORO to identify and repair virus damage to Windows OS files.

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.