Snort mailing list archives
Snort Evasion?
From: IDS Expect <robertgoldman2000 () yahoo com>
Date: Sun, 17 Mar 2002 14:28:41 -0800 (PST)
Hi, I have been examining the snort 1.8.4 source code and I think I found a very simple way to evade Snort if and when stream4 is in use. It seems like in spp_stream4.c, FlushStream() will ignore all packets if base_seq is zero. Well, base_seq is set to the sequence number of the first data byte. What if the attacker initializes her TCP connection's sequence number to 0xffffffff. This well make base_seq zero and Snort will further ignore any data on this connection. Am I right? --rob __________________________________________________ Do You Yahoo!? Yahoo! Sports - live college hoops coverage http://sports.yahoo.com/ _______________________________________________ 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
Current thread:
- Snort Evasion? IDS Expect (Mar 17)
- Re: Snort Evasion? Martin Roesch (Mar 17)