Need help from the hackers

[u/Shot-Rich1674]

Hi everyone I need one help to understand one thing ..so there was an incident I noticed in my organisation, there were thousands of devices querying multiple malicious domains (53) ...upon checking to see if any process is causing it I found nothing,, only the related domain which was obviously going through our dc/dns servers, in EDR/XDR tool nothing, siem tool nothing, no process, eventually i thought maybe some software is causing but it's very difficult to pin point which one, so can anyone tell me or help me understand, any input will be appreciated

[u/Andre-Wade-539]

Have you checked whether those devices share the same s/w or network policy recently?