Pen testing
C2
Onimai is a Remote Access Trojan (RAT) that gives attackers control over infected systems, allowing them to monitor, exfiltrate data and execute commands. It has evolved, version 1.7.1 has added more features to make it more powerful and stealthy.
Onimai RAT has been improved; it has real-time desktop monitoring, secure file transfer, hidden VNC, UAC bypass, encrypted communication, anti-debugging and anti-sandbox techniques, remote shell access, persistent access, and .NET and Visual Basic code execution. All these features make Onimai RAT a powerful tool for cybercriminals to have full control and surveillance over the targeted system.
Infection and Distribution
Onimai RAT is distributed through deceptive means like phishing emails, malicious attachments, or downloads from untrusted sources. Once executed, it can download more malicious scripts via PowerShell commands and compromise the system.
Operational Impact
Once infected, Onimai RAT gives attackers full control over the victim’s system, to steal data, monitor and deploy more malware. Its stealth features make detection and removal hard; it’s a big risk to individuals and organizations.
There are no specific variants of Onimai RAT reported. But user reports shows that it manifests as processes like “$nya-onimai3” which displays error message upon system startup.
Regular System Scans: Use updated antivirus and anti-malware to detect and remove threats.
Be cautious with Email Attachments: Avoid opening attachments or clicking links from unknown or untrusted sources.
Software Updates: Keep your OS and all software up to date to patch vulnerabilities.
User Education: Be informed about phishing and other common cyber threats to recognize and avoid them.
Onimai RAT doesn’t seem to target specific industries. Its distribution method is broad, it can affect any sector and individuals indiscriminately.
The origin of Onimai RAT is unknown, but on Reddit, it’s being discussed that it’s associated with Vietnamese threat actors.

