Triggers when a series of TCP FIN packets have been sent to the same destination port on a number of different hosts. This could, for example, be a sweep of many hosts to find out which ones can receive mail or telnet sessions.
This is indicative that a reconnaissance sweep of your network may be in progress. This may be the prelude to a more serious attack.
Exclude internal networks as sources.
The host sweep signatures 3030 and 3032 detect behaviors that should not be observed from sources outside the local network but are normal behaviors for sources from within the local network.
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