New HollowGraph Malware Abuses Microsoft 365 Calendar for C&C Communication
Part of a larger toolkit, HollowGraph uses a compromised 365 account’s calendar as a two-way dead-drop. The post New HollowGraph Malware Abuses Microsoft 365 Calendar for C&C Communication appeared first on SecurityWeek.
A recently discovered piece of malware abuses the Microsoft 365 calendar for command-and-control (C&C) communication, Group-IB reports.
Dubbed HollowGraph, the malware is believed to be part of a larger toolkit and is likely linked to Cavern Manticore, an Iran-nexus threat actor that Check Point detailed earlier this month.
The malware’s communication mechanism relies on the Microsoft Graph API and a compromised 365 account in Israel to hide its C&C communication within legitimate traffic.
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