A sophisticated campaign using Winos 4.0 malware targets Windows users in Chinese-speaking environments through fake installers.
The attack starts with phishing emails posing as official notifications, leading users to download malicious software installers.
The malware employs a multi-stage loader called Catena to silently introduce Winos 4.0 into memory.
Security experts note the campaign initiated in early 2025, with Winos 4.0 establishing persistence, exploiting privileges, and communicating with command-and-control servers.
Winos 4.0's delivery mechanism involves disabling Windows Defender, using reflective DLL injection for stealthy execution, and maintaining persistence through various methods.
The malware, also known as ValleyRAT, offers remote control features like shell access, keylogging, data exfiltration, and cryptocurrency theft.
It connects to attacker-controlled servers for encrypted communication, indicating a strategic shift towards long-term espionage by the Void Arachne group.
Security advice includes installing software from trusted sources, updating systems regularly, using advanced threat detection tools, and educating users about phishing emails.