GrimResource - Microsoft Management Console for initial access and evasion

Elastic Security researchers describe 'GrimResource', a novel technique that leverages an XSS issue in apds.dll via crafted MSC files to execute arbitrary JavaScript in mmc.exe, chain into DotNetToJScript and a PASTALOADER .NET loader, and ultimately deploy a Cobalt Strike payload; the report includes behavioral detections (EQL), a YARA rule, and observable hashes for detection and hunting.