Graph API – CyberSecurityBoard

Malware

HollowGraph Malware Uses Microsoft 365 Calendar Events Dated 2050 for C2 and Data Exfiltration

Group-IB has discovered a new espionage implant named HollowGraph that hijacks Microsoft 365 calendars for command-and-control (C2) and data exfiltration. The malware,…

C2 Cavern Cavern Manticore Check Point

July 20, 2026

Malware

HollowGraph Malware Overview

HollowGraph is a .NET DLL espionage implant discovered by Group-IB that uses Microsoft 365 calendar events dated to 2050 for command-and-control and…

espionage Graph API HollowGraph malware

July 20, 2026

Malware

GraphSpy: Post-Exploitation Tool for Microsoft 365 and Entra

GraphSpy is a tool used for post-exploitation of Microsoft 365 and Entra environments, often integrated into PhaaS platforms like DEBULL. It enables…

Data Exfiltration Entra Graph API GraphSpy

July 7, 2026