A Powerful .NET Spyware Creating Backdoor and Records Full videos, Spying on User Activities

A New.NET Spyware Discovered as “Backdoor.DuBled”  has some sophisticated functions unlike other spyware,it can also records full videos, spying on user activities ,and send it across to an attacker.

Recent Malware are embedded with legitimate applications that used to evade malware to get caught up by the AV Vendors.This .NET Spyware incorporate legitimate applications in their malicious package and Downlaod a legitimate ffmpeg.

It is also have ability to saving keystrokes and logging the running applications.

According to Malwarebytes, Drop the JS executable into  %TEMP% Folder and executable installs itself creating its own Folder in  %APPDATA%. and an Additional copy of the malware is also dropped in the startup folder.

After further analyze,Researchers found that dropped files contents are not Encrypted And also malware downloads legitimate applications: Rar.exe, ffmpeg.exe.

Spyware Communication

Thi spyware communicate with command & control server over TCP using port 98 and server initiate the “idjamel” comclient.

Once client received  Command form server , client responds the information that collected about the infected victims machine.

Malware sharing the information including machine name/username, the operating system installed, and a list of running processes.

Malicious package of the  payload is the layer containing all the malicious features and its not well obfuscated so researchers easily Decompiled it.

Recording Videos

Main Motivation of this Spyware is, spying the victims and creating the Backdoor for the infected the machine.

Mainly Targetting  is to steal the Bank information form the Victims by Recording videos while the Victims browsing the bank websites.

Malwarebytes said, Periodically, the check is made, whether the target from the list has been open in the browser. In case if it was detected, the malware deploys video recorder.

“The malware also has a feature of making simple screenshots, saved as JPG. The pictures and the captured logs are periodically compressed by the Rar application, and then also sent to the CnC “

The mentioned malware family was first discovered in 2015 by MalwarHunterTeam.

Analyzed samples

1. 2a07346045558f49cad9da0d249963f1 – dropper (JS)
2. 049af19db6ddd998ac94be3147050217 – dropped executable (C#)
3. 9c9f9b127becf7667df4ff9726420ccb – loader
4. 85d35dd33f898a1f03ffb3b2ec111132 – final payload

Downloaded plugins:

1. e907ebeda7d6fd7f0017a6fb048c4d23 – remotedesktop.dll
2. d628d2a9726b777961f2d1346f988767 – processmanager.dll