[Op Report] PackClient: Hands-on-Keyboard with a new C2 Framework

A Chinese-speaking threat actor used the new PackClient RAT for initial access, then covertly leveraged a legitimate, vendor-signed endpoint management platform (ManageEngine Endpoint Central) to gain persistent, full-spectrum control over a critical infrastructure consultancy's network—demonstrating a stealthy handoff from commodity malware to trusted IT tools for deep post-compromise operations.