Geek's Advice

LEEX ransomware comes from the largest crypto-virus family called STOP/DJVU

LEEX ransomware is a malicious computer virus that is the 308th variant of STOP/DJVU family. This virus is set to encrypt all files on victim’s computer using RSA Salsa20 cryptography ciphers and mark each file with additional .leex extension. For example, file originally called 1.jpg appears as 1.jpg.leex after encryption. Once modified, files can no longer be opened. The malware operators also set the virtual extortion tool to save ransom notes called _readme.txt in every affected folder. This note suggests that the victim’s files have been encrypted using ‘strongest encryption and unique key’ and that the only way to decrypt .leex files is to pay a ransom for cyber criminals. According to them, the victim needs to write to manager@mailtemp.ch or helpmanager@airmail.cc within 3 days. The criminals suggest a 50% discount on decryption price (meaning that it will cost $490) if the victim contacts them and pays within this time period. Otherwise, the decryption price will be $980.

LEEX ransomware is developed to be a virtual extortion tool. Its primary aim is to scan the infected system for target files (ones that match ones from its target list according to file type). Considering that computer users keep valuable information on their computers, the attackers hope to extort the victim by taking such information hostage. Therefore, the virus can lock images, videos, documents, archives and other important documents in no time. Its algorithm targets to encrypt only the first 150KB of file (this is done to ensure that the file gets corrupted but also to shorten the time required to affect all files on the system). This also allows to restore some audio/video files with minimal loss at the beginning of file as explained in this guide.

The _readme.txt note left by the criminals suggest that the victim has to write to the attackers and pay $490 in 3 days in order to receive file decryption software and unique decryption key. However, if the victim misses this timeframe and decides to pay later, the criminals demand twice the initial amount – $980. Of course, the attackers want to receive the ransom in cryptocurrency to remain anonymous. As a result, the criminals instruct the victim to purchase Bitcoins worth the corresponding amount of US dollars and transfer it to their wallets. To encourage the victim to pay sooner, the criminals even suggest testing the decryption software first – they allow sending one small file to them for test decryption.

However, paying a ransom to cybercriminals is never a good idea. Geek’s Advice team as well as FBI do not recommend paying up due to the following reasons:

• Cybercriminals can promise you anything in order to make you transfer the ransom to them. However, there is no guarantee that they will do what they promised as well. In other words, you might spend your money for nothing.
• Ransomware-type viruses earn millions of US dollars to malevolent actors each year. The money in this industry is one of the key factors that lures other people to join in. Please, do not fund cybercriminals’ operations by paying a ransom!
• Paying a ransom to cybercriminals might be illegal in your country of residence.
• Variants of STOP/DJVU ransomware family such as LEEX virus run AZORULT Trojan on the infected computer. This is a well-known information stealer which we will describe in detail later.

Ransomware damage to your computer explained

LEEX ransomware begins the attack by launching a fake Windows update prompt that displays a progress bar (winupdate.exe file). According to our team experts, this is done to deceive the victim and justify the sudden computer slowdown which is actually caused by ransomware’s processes running in the background. During the encryption procedure, the virus also saves _readme.txt in every folder to ensure that the victim really notices it and opens it. Next, the ransomware eliminates Volume Shadow Copies from the computer, which guarantees that the victim won’t succeed in restoring encrypted files using System Restore points. The ransomware executes the following command via CMD to do this:

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

Next, the ransomware adds a list of domains to Windows HOSTS file and maps them to localhost IP so that the victim couldn’t access the website. This simply tells your computer system to use a particular IP address (your localhost IP) instead of whichever IP your DNS server resolves to when you try to access particular website via web browser. Most likely you’re going to see DNS_PROBE_FINISHED_NXDOMAIN error in your browser as well. It has been noticed that the ransomware attempts to block websites such as microsoft.com and other computer-related domains or online help forums. It is believed that the ransomware operators do not want the victim to find any helpful online. Lastly, the virus drops bowsakkdestx.txt or similarly named file that contains victim’s public encryption key and personal ID (also can be found in PersonalID.txt file dropped by the virus).

The ransomware might also execute Azorult Trojan on the system. This threat is widely known information stealer capable of:

• Allowing remote attacker to control the computer;
• 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.

That said, you should remove LEEX ransomware virus and related threats in no time to ensure that no additional damage can be done to your system. To professionally secure your computer, we strongly advise using INTEGO Antivirus first. Then scan with RESTORO to repair virus damage on Windows OS files.

Ransomware Summary

Ransomware distribution tricks: avoid getting infected

Ransomware-type viruses are typically distributed in a form of malicious email attachments, compromised ad networks, illegal torrent downloads or fake tools. In this particular case, STOP/DJVU variant LEEX file virus is distributed mainly via illegal online downloads. Most of the victims infected with this malware report downloading the virus along with software crack. These as well as keygens or tools like KMSPico are well-known malware droppers. Computer users who are looking for such tools in order to activate paid software versions for free risk running into a trap set up by malware distributors. They complement such downloads with malicious scripts that connect to compromised domains and download ransomware payload to the system.

What makes this distribution technique so successful is that computer users tend to ignore antivirus warnings’ about potentially malicious downloads detected. There is a popular misconception that software cracks are marked as malicious by default. Therefore, users proceed to open such downloads and install them. However, even if everything seems fine at the first sight, your computer might still get infected with silent and hard-to-detect malware such as miners or malware that is set to execute after a while.

We strongly advise you to head to official and legitimate websites to download programs from. Remember that legitimate software developers work hard to provide you with highly functional and useful programs. We suggest that supporting them instead of supporting criminals who aim to take your valuable information hostage.

Another tricky technique that cybercriminals use is sending deceptive email spam to potential victims. The attackers get their hands on publicly available email lists (for instance those made available via various data leaks) which they use to send mass spam. Such emails are designed to deceive the victim and trick one into believing that the message comes from a trustworthy party (such as well-known company like eBay or Amazon). There are always some attachments or links involved that the victim ‘needs’ to open and review. Unfortunately, clicking on those can instantly infect the computer.

Nowadays, it can be hard to identify whether the email sender is trustworthy, especially with the usage of email spoofing techniques. Our general advice is to only open emails that you waited for and expected to receive. Do not let your curiosity take over and avoid opening suspicious messages that come from someone who wasn’t supposed to write you.

Finally, STOP/DJVU ransomware victims should beware that other ransomware families such as ZORAB have been uploading fake decryption tools to various online sites. Be careful as these are packed with other file-encrypting threats that will cause double-encryption of your files if you decide to download and open them.

Remove LEEX ransomware virus and decrypt your files

Now that you have fallen victim to a ransomware attack, we strongly recommend you to take actions to secure your computer first. Therefore, you will need to eliminate all malware using professional software while in Safe Mode with Networking (as explained in the free guide below). We suggest using INTEGO Antivirus, an excellent Windows security software that scores no less than 99.5% malware detection rate in independent lab tests. Next, download and run RESTORO to repair virus damage on your Windows OS files.

Once LEEX ransomware virus removal is complete, we strongly suggest taking the following actions:

• Report 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.
• Use these 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.