Abyssos: Technical Analysis of a New Modular RAT

In late June 2026, a new malware family named Abyssos was identified, representing a modular remote administration tool written in C++ with diverse capabilities including credential theft, file exfiltration, and remote access via VNC. The malware employs LLVM-based obfuscation techniques such as control flow flattening and string encryption to evade security products and complicate analysis. Abyssos uses a custom TCP protocol with AES-GCM encryption for network communication and supports numerous commands for system manipulation, data collection, and module deployment. It features anti-analysis mechanisms detecting hypervisors and security tools, though recent versions lack these checks. The malware demonstrates active development with multiple versions implementing different obfuscation passes, suggesting continued evolution of its capabilities and evasion techniques.