LoFP LoFP / trusted applications for managing calendars and reminders.

Techniques

Sample rules

Suspicious Calendar File Modification

Description

Identifies suspicious modifications of the calendar file by an unusual process. Adversaries may create a custom calendar notification procedure to execute a malicious program at a recurring interval to establish persistence.

Detection logic

event.category:file and host.os.type:macos and event.action:modification and
  file.path:/Users/*/Library/Calendars/*.calendar/Events/*.ics and
  process.executable:
  (* and not
    (
      /System/Library/* or
      /System/Applications/Calendar.app/Contents/MacOS/* or
      /System/Applications/Mail.app/Contents/MacOS/Mail or
      /usr/libexec/xpcproxy or
      /sbin/launchd or
      /Applications/*
    )
  )