Analysis of APT37 NarwhalRAT Leveraging MS-Themed Phishing and Dead-drop C2

Description

A sophisticated Python-based RAT targeting Korean users through spear phishing emails disguised as Microsoft security alerts. The attack chain employs LNK files embedded in ZIP archives, BAT-based obfuscation, and multi-stage loaders culminating in NarwhalRAT deployment. This advanced malware features keylogging, screen capture, microphone recording, and USB data collection capabilities. It utilizes a dual C2 infrastructure combining Korean relay servers (daehoat.com, novel21.co.kr) with pCloud API as a dead-drop resolver. The malware creates encrypted configuration files, implements anti-VM techniques, and establishes persistence through scheduled tasks. It operates as a manually-controlled RAT with selective function activation via C2 commands, employing in-memory execution to evade file-based detection.