Remcos RAT is a type of Remote Access Trojan used for unauthorized access and control of a computer system.
It allows threat actors to perform various malicious activities like:-.
Cybersecurity researchers at Uptycs recently discovered that the threat group UAC-0050 had been actively using the Remcos RAT pipe method for evasion to target Ukraine.
The threat actors have implemented this pipe method for interprocess communication.
Lnk file on December 21, 2023, prompting cybersecurity researchers to investigate.
They found UAC-0050 using RemcosRAT in a focused cyber operation against Ukrainian government agencies.
An LNK file initiates HTA download, containing a VBS script that triggers a PowerShell script to download word update.
Exe, which shares the data through a pipe that leads to RemcosRAT in explorer.
The.lnk file, a Windows shortcut, is the investigation's starting point.
Lnk file checks antivirus info, which alters 'the Windows Defender' to avoid an 'exit' statement, and this ensures script continuity.
The.lnk file concludes with an obfuscated URL executed via MSHTA after deobfuscation.
Besides this, after deobfuscating the VBScript, a PowerShell script is uncovered.
Deobfuscation reveals $hQkGkZK, which leads to another PowerShell script with encoded data.
Uptycs flags suspicious PowerShell activities that help in tracking payloads from:-.
The malware ensures persistence via the LNK file in startup, launching fmTask dbg.
Exe undergoes decryption that utilizes pipes to move data to cmd.
Exe by executing Remcos RAT. The RemcosRAT is extracted from the cmd.
Exe memory and then decrypts the RC4-encrypted data in the payload's Resource section using CyberChef.
The identified Remcos version 4.9.2 Pro gathers the victim's info, such as computer name and username.
From the following web browsers, the cookies and login data were removed by the RemcosRAT:-.
This Cyber News was published on gbhackers.com. Publication date: Fri, 05 Jan 2024 10:43:04 +0000