[Snort-users] snort decode warning tcp data offset is less than 5

Todd Wease twease at ...1935...
Tue Nov 27 10:15:55 EST 2007


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.
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