Hackers Use Fake Zoom Installers to Install Backdoor and Devil Shadow Botnet on Windows Computers
Hackers taking advantage of the video conferencing apps like Zoom to infect systems with malicious routines.
Security researchers from Trend Micro observed two malware samples that pose as Zoom installers but when decoded it contains malware.
The malicious fake installer not distributed through official distribution channels.
Fake Zoom Installers
With the two malware samples, one found installing a backdoor that allows attackers to gain access remotely, another one is the Devil Shadow botnet in devices.
The malicious installer resembles closer to the official version, it contains encrypted files that will decrypt the malware version.
The malware kills all the running remote utilities upon installation and opens TCP port 5650 to gain remote access to the infected system.
It notifies the command and control (C&C) server that email has been set up, stolen credentials, and flag the infected machine ready to access. The fake installer also runs an official zoom installer to avoid suspicion.
Another sample observed by researchers installs Devil Shadow Botnet, the infection starts with the malicious installer with the file named pyclient.cmd which contains malicious commands.
With this sample also the threat actors include a copy of the official Zoom installer to deceive the victims.
The tampered app installer deploys malicious archive and codes, and the commands for persistence and communication.
The malware used to send gathered information to its C&C every 30 seconds every time the computer is turned on.
In another campaign, attackers repackaged the legitimate zoom installer with WebMonitor RAT. The infection starts with downloading the malicious file ZoomIntsaller.exe from malicious sources.
Due to coronavirus pandemic, many companies around the world asked employees to work from home, which increases the usage of video conferencing apps and it is heavily targeted by attackers.