Have you checked the source and destination?
MALWARE-CNC -- Snort has detected a Comand and Control (CNC) rule violation, most likely for commands and calls for files or other stages from the control server. The alert indicates a host has been infiltrated by an attacker, who is using the host to make calls for files, as a call-home vector for other malware-infected networks, for shuttling traffic back to bot owners, etc
Rule Explanation
Alerts on traffic produced by Win.Trojan.ModernLoader malware to or from the C2 server.
What To Look For
Alerts on traffic produced by Win.Trojan.ModernLoader malware to or from the C2 server.
I am not a Cisco Meraki employee. My suggestions are based on documentation of Meraki best practices and day-to-day experience.
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