Triggers when a series of fragmented TCP packets with none of the SYN, FIN, ACK, or RST flags set have been sent to a number of different hosts on any port. 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. The use of this packet is abnormal, as is the use of fragmentation, and could indicate an attempt to conceal the sweep.
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