This signature fires when a series of TCP SYN packets have been sent from one single host to a number of different hosts. This could, for example, be an attempt to map the network.
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.
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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