Snort mailing list archives
Re: Stream4
From: Martin Roesch <roesch () sourcefire com>
Date: Mon, 28 Jan 2002 21:50:22 -0500
On 1/28/02 5:43 PM, "Matt Jonkman" <matt () jonkmans com> wrote:
Where can I find more detailed documentation on stream4? Specifically, I'm wondering if the setect_scans functionality replaces the abilities of the portscan preprocessor.
Not yet. Right now it detects stealth scans and nmap fingerprint scanning, but we don't have the code in to statefully pick up SYN scans. IMHO, I think we should move to post-process detection of SYN/UDP scans by utilizing the keep_stats function that stream4 supports, there's no burning need for real-time detection of SYN scans in the general case (but that's just me talking...)
We'd prefer to use the stream4 plugin as it formats database entries correctly with source and dest IP making things much easier to research. I can make stream4 alert on a very overt xmas scan, but nothing for a syn or tcp scan. Are there parameters to set to make it more sensitive?
Nope. We've toyed with the idea of doing things like looking for short sessions (SYN-SYNACK-RST, full connect with RST) and detecting just them, we've also toyed with the idea of doing straight rate detection for SYN packets. Both methods have their ups and downs from a performance and memory management perspective, which is why I've held off on implementing them. If you want to take a stab at implementing it, I'll take a look at what you come up with. -Marty -- Martin Roesch - Founder/CEO Sourcefire Inc. - (410) 552-6999 Sourcefire: Professional Snort Sensor and Management Console appliances roesch () sourcefire com - http://www.sourcefire.com Snort: Open Source Network IDS - http://www.snort.org _______________________________________________ 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 log question Lookman Fazal (Jan 28)
- Stream4 Matt Jonkman (Jan 28)
- Re: Stream4 Martin Roesch (Jan 28)
- Re: Stream4 Matt Jonkman (Jan 28)
- Re: Stream4 Phil Wood (Jan 28)
- Re: Stream4 Martin Roesch (Jan 28)
- Stream4 Matt Jonkman (Jan 28)
- Re: snort log question Martin Roesch (Jan 28)