What is JSSLOADER?
JSSLOADER is the name of a Remote Access Trojan (RAT) that is capable of exfiltrating data, executing commands, downloading other malware, auto-updating itself and preventing itself from being debugged (analyzed). It is known that JSSLOADER is mostly used by the group of cyber criminals called FIN7.
At first, JSSLOADER collects (exfiltrates) data such as AD (Active Directory) information, domain name, desktop files, host name, logical drives, network information, running processes, system information, user name and sends it to a certain URL address.
Then attackers use it to send CMD commands from C2 (Command and control server), that coud include commands to write and execute executable file, rewrite JSSLOADER with its updated version, uninstall JSSLOADER (and remove the persistency, terminate its process), execute a PowerShell command, write and execute a DLL file.
Research shows that one of the main commands that attackers execute via JSSLOADER is "Cmd_RAT" that executes a Takeout script which loads and executes Carbanak, data-stealing banking malware. Typically, malware of this type is used to steal financial information (like credit car details, bank account numbers), login credentials and/or other sensitive information.
|Name||JSSLOADER Remote Access Trojan|
|Threat Type||Remote Access Trojan|
|Detection Names||Avast (Other:Malware-gen [Trj]), BitDefender (VBS.Heur.Maltzur.1.013F4BB5.Gen), Emsisoft (VBS.Heur.Maltzur.1.013F4BB5.Gen (B)), Kaspersky (HEUR:Trojan-Downloader.Script.Generic), Microsoft (TrojanDownloader:VBS/Qakbot.AR!MTB), Full List (VirusTotal)|
|Malicious Process Name(s)||MimiHealth (its name may vary)|
|Symptoms||Remote Administration Trojans are designed to stealthily infiltrate the victim's computer and remain silent, and thus no particular symptoms are clearly visible on an infected machine.|
|Distribution methods||Infected email attachments, malicious online advertisements, social engineering, software 'cracks'.|
|Damage||Stolen passwords and banking information, identity theft, the victim's computer added to a botnet.|
|Malware Removal (Windows)||
To eliminate possible malware infections, scan your computer with legitimate antivirus software. Our security researchers recommend using Combo Cleaner.
In conclusion, cyber criminals behind JSSLOADER can use it to collect certain data (including files placed on desktop) and execute commands that could be used to install not only the aforementioned banking malware but some other malicious software as well.
More examples of RATs are VoidRAT, IceRAT and PyXie. In most cases RATs are used to remotely access infected computers and then steal sensitive information and/or infect computers with some other malware.
How did JSSLOADER infiltrate my computer?
It is known that JSSLOADER is distributed via malspam emails. Typically, such emails contain some malicious attachment or a download link for a malicious file. To trick recipients into opening a malicious file cyber criminals disguise such emails as important, official letters from legitimate companies, organizations.
More examples of ways to distribute malware are to use untrustworthy software download sources (like Peer-to-Peer networks such as torrents, eMule, freeware download websites, free file hosting websites, etc.), third party installers, certain Trojans, unofficial software activation and fake software updating tools.
How to avoid installation of malware?
Software (and files) should be downloaded only from official, legitimate pages and via direct download links. Other sources, tools should not be trusted. Attachments and website links in irrelevant emails that are received from unknown, suspicious addresses should not be opened as well.
Even if such emails look like they are sent from legitimate companies, they may be used to distribute malware. Installed software has to be updated and/or activated with tools that are provided by official software developers. Other (third party, unofficial) tools can be and often are used to distribute malware.
Also, it is not legal to use 'cracking' tools (unofficial activation tools) to activate any licensed software, ore use pirated software. The operating system should have a reputable antivirus or anti-spyware software installed on it ant is should be scanned for threats regularly.
If you believe that your computer is already infected, we recommend running a scan with Combo Cleaner Antivirus for Windows to automatically eliminate infiltrated malware.
JSSLOADER running in Task Manager as "MimiHealth" (its name may vary):
Example of a malicious Microsoft Word document used to inject JSSLOADER RAT into the system:
Instant automatic malware removal:
Manual threat removal might be a lengthy and complicated process that requires advanced computer skills. Combo Cleaner is a professional automatic malware removal tool that is recommended to get rid of malware. Download it by clicking the button below:
- What is JSSLOADER?
- STEP 1. Manual removal of JSSLOADER malware.
- STEP 2. Check if your computer is clean.
How to remove malware manually?
Manual malware removal is a complicated task - usually it is best to allow antivirus or anti-malware programs to do this automatically. To remove this malware we recommend using Combo Cleaner Antivirus for Windows.
If you wish to remove malware manually, the first step is to identify the name of the malware that you are trying to remove. Here is an example of a suspicious program running on a user's computer:
If you checked the list of programs running on your computer, for example, using task manager, and identified a program that looks suspicious, you should continue with these steps:
Download a program called Autoruns. This program shows auto-start applications, Registry, and file system locations:
Restart your computer into Safe Mode:
Windows XP and Windows 7 users: Start your computer in Safe Mode. Click Start, click Shut Down, click Restart, click OK. During your computer start process, press the F8 key on your keyboard multiple times until you see the Windows Advanced Option menu, and then select Safe Mode with Networking from the list.
Video showing how to start Windows 7 in "Safe Mode with Networking":
Windows 8 users: Start Windows 8 is Safe Mode with Networking - Go to Windows 8 Start Screen, type Advanced, in the search results select Settings. Click Advanced startup options, in the opened "General PC Settings" window, select Advanced startup. Click the "Restart now" button.
Your computer will now restart into the "Advanced Startup options menu". Click the "Troubleshoot" button, and then click the "Advanced options" button. In the advanced option screen, click "Startup settings". Click the "Restart" button. Your PC will restart into the Startup Settings screen. Press F5 to boot in Safe Mode with Networking.
Video showing how to start Windows 8 in "Safe Mode with Networking":
Windows 10 users: Click the Windows logo and select the Power icon. In the opened menu click "Restart" while holding "Shift" button on your keyboard. In the "choose an option" window click on the "Troubleshoot", next select "Advanced options". In the advanced options menu select "Startup Settings" and click on the "Restart" button.
In the following window you should click the "F5" button on your keyboard. This will restart your operating system in safe mode with networking.
Video showing how to start Windows 10 in "Safe Mode with Networking":
Extract the downloaded archive and run the Autoruns.exe file.
In the Autoruns application, click "Options" at the top and uncheck "Hide Empty Locations" and "Hide Windows Entries" options. After this procedure, click the "Refresh" icon.
Check the list provided by the Autoruns application and locate the malware file that you want to eliminate.
You should write down its full path and name. Note that some malware hides process names under legitimate Windows process names. At this stage, it is very important to avoid removing system files. After you locate the suspicious program you wish to remove, right click your mouse over its name and choose "Delete".
After removing the malware through the Autoruns application (this ensures that the malware will not run automatically on the next system startup), you should search for the malware name on your computer. Be sure to enable hidden files and folders before proceeding. If you find the filename of the malware, be sure to remove it.
Reboot your computer in normal mode. Following these steps should remove any malware from your computer. Note that manual threat removal requires advanced computer skills. If you do not have these skills, leave malware removal to antivirus and anti-malware programs.
These steps might not work with advanced malware infections. As always it is best to prevent infection than try to remove malware later. To keep your computer safe, install the latest operating system updates and use antivirus software.
To be sure your computer is free of malware infections, we recommend scanning it with Combo Cleaner Antivirus for Windows.