Another issue affecting onPrem Exchange servers (bug affect 2016 & 2019) has been made public today where emails are trapped in the transport queues, this is related to a date check failure with the change of the new year. Microsoft has confirmed this is not a security related issue.
Microsoft is working on a patch and has released a workaround posted here.
Guy Bruneau IPSS Inc.
My Handler Page
gbruneau at isc dot sans dot edu
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