Snort mailing list archives
Re: snort decode warning tcp data offset is less than 5
From: Todd Wease <twease () sourcefire com>
Date: Tue, 27 Nov 2007 10:15:55 -0500
This alert implies that the TCP offset field contains a value that is less than the size of a minimum TCP header which is 20 bytes. The TCP offset field should contain a value that represents the number of 4 byte words that make up a TCP header, so 5 * 4 = 20 - the minimum TCP header length. This is most likely something you want to investigate. Todd The New York NOC Inc. wrote:
Hi, I keep gettings tons of these alerts from varying ip addresses to one destination ip. (snort_decoder) WARNING: TCP Data Offset is less than 5! How do I stop these alerts? Thanks AJ =========================== The New York NOC Inc. Dedicated Servers / VPS / Colocation www.thenynoc.com <http://www.thenynoc.com> ------------------------------- ------------------------------------------------------------------------ ------------------------------------------------------------------------- This SF.net email is sponsored by: Microsoft Defy all challenges. Microsoft(R) Visual Studio 2005. http://clk.atdmt.com/MRT/go/vse0120000070mrt/direct/01/ ------------------------------------------------------------------------ _______________________________________________ Snort-users mailing list Snort-users () lists sourceforge net Go to this URL to change user options or unsubscribe: https://lists.sourceforge.net/lists/listinfo/snort-users Snort-users list archive: http://www.geocrawler.com/redir-sf.php3?list=snort-users
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Current thread:
- snort decode warning tcp data offset is less than 5 The New York NOC Inc. (Nov 26)
- Re: snort decode warning tcp data offset is less than 5 Joel Esler (Nov 26)
- Re: snort decode warning tcp data offset is less than 5 Todd Wease (Nov 27)