Venus Ransomware targets publicly exposed Remote Desktop services

Threat actors behind the relatively new Venus Ransomware are hacking into publicly-exposed Remote Desktop services to encrypt Windows devices.

Venus Ransomware appears to have begun operating in the middle of August 2022 and has since encrypted victims worldwide. However, there was another ransomware using the same encrypted file extension since 2021, but it is unclear if they are related.

BleepingComputer first learned of the ransomware from MalwareHunterTeam, who was contacted by security analyst linuxct looking for information on it.

Linuxct told BleepingComputer that the threat actors gained access to a victim's corporate network through the Windows Remote Desktop protocol.

Another victim in the BleepingComputer forums also reported RDP being used for initial access to their network, even when using a non-standard port number for the service.

How Venus encrypts Windows devices

When executed, the Venus ransomware will attempt to terminate thirty-nine processes associated with database servers and Microsoft Office applications.

taskkill, msftesql.exe, sqlagent.exe, sqlbrowser.exe, sqlservr.exe, sqlwriter.exe, oracle.exe, ocssd.exe, dbsnmp.exe, synctime.exe, mydesktopqos.exe, agntsvc.exe, isqlplussvc.exe, xfssvccon.exe, mydesktopservice.exe, ocautoupds.exe, agntsvc.exe, agntsvc.exe, agntsvc.exe, encsvc.exe, firefoxconfig.exe, tbirdconfig.exe, ocomm.exe, mysqld.exe, mysqld-nt.exe, mysqld-opt.exe, dbeng50.exe, sqbcoreservice.exe, excel.exe, infopath.exe, msaccess.exe, mspub.exe, onenote.exe, outlook.exe, powerpnt.exe, sqlservr.exe, thebat64.exe, thunderbird.exe, winword.exe, wordpad.exe

The ransomware will also delete event logs, Shadow Copy Volumes, and disable Data Execution Prevention using the following command:

wbadmin delete catalog -quiet && vssadmin.exe delete shadows /all /quiet && bcdedit.exe /set {current} nx AlwaysOff && wmic SHADOWCOPY DELETE

When encrypting files, the ransomware will append the .venus extension, as shown below. For example, a file called test.jpg would be encrypted and renamed test.jpg. Venus.

Files encrypted by the Venus Ransomware - Source: BleepingComputer

 

In each encrypted file, the ransomware will add a 'goodgamer' filemarker and other information to the end of the file. It is unclear what this additional information is at this time.

The ransomware will create an HTA ransom note in the %Temp% folder that will automatically be displayed when the ransomware is finished encrypting the device.

As you can see below, this ransomware calls itself "Venus" and shares a TOX address and email address that can be used to contact the attacker to negotiate a ransom payment. At the end of the ransom note is a base64 encoded blob, which is likely the encrypted decryption key.

Venus Ransomware ransom note - Source: BleepingComputer

 

At this time, the Venus ransomware is fairly active, with new submissions uploaded to ID Ransomware daily.

As the ransomware appears to be targeting publicly-exposed Remote Desktop services, even those running on non-standard TCP ports, it is vital to put these services behind a firewall.

Ideally, no Remote Desktop Services should be publicly exposed on the Internet and only be accessible via a VPN.