Snort mailing list archives
Re: Starting off now it's running
From: paul.guijt () gmail com
Date: Sun, 16 Apr 2017 17:20:40 +0200
Hi Al, Thanks for your suggestion! It put me on a better track. At first I had completely removed 'small_segments 0 bytes 0,' from snort.conf. But then I thought that removal to be brutal, because I only wanted to suppress a specific alert. I found out that I can suppress alerts through suppress in threshold.conf, and am now exploring that. Regards, Paul -----Oorspronkelijk bericht----- Van: Al Lewis (allewi) [mailto:allewi () cisco com] Verzonden: zondag 16 april 2017 03:51 Aan: Paul Guijt <paul.guijt () gmail com>; snort-users () lists sourceforge net Onderwerp: Re: [Snort-users] Starting off now it's running A good place to start would be in the manual/README files. In this particular case check out the doc/README.stream5 file and see the section on “small segments”. Copied below: small_segments <num1> bytes <num2> [ignore_ports port list] - Configure the maximum small segments queued. This feature requires that detect_anomalies be enabled. num1 is the number of consecutive segments that will trigger the detection rule. The default value is "0" (disabled),with a maximum of "2048”. num2 is the minimum bytes for a segment to be considered "small". The default value is "0" (disabled), with a maximum of "2048”. ignore_ports is optional, defines the list of ports in which will be ignored for this rule. The number of ports can be up to "65535”. Example: small_segments 3 bytes 15 ignore_ports 33 44 55 A message is written to console/syslog when this limit is enforced. The generated alert is 129:12 Thanks! Albert Lewis ENGINEER.SOFTWARE ENGINEERING SOURCEfire, Inc. now part of Cisco Email: allewi () cisco com On 4/15/17, 4:18 PM, "Paul Guijt" <paul.guijt () gmail com> wrote:
Hi all, I have Snort now running on my Raspberry in IDS mode (thanks Don Mizutani!), great. It spits out in /var/log/snort/alerts reports like [**] [129:12:1] Consecutive TCP small segments exceeding threshold [**] [Classification: Potentially Bad Traffic] [Priority: 2] 04/15-21:21:36.514707 192.168.178.100:2049 -> 192.168.178.28:698 TCP TTL:64 TOS:0x0 ID:18139 IpLen:20 DgmLen:128 DF ***AP*** Seq: 0xD8616620 Ack: 0x6982D5A5 Win: 0x103A TcpLen: 32 TCP Options (3) => NOP NOP TS: 1942222394 4294959044 This is an alert about friendly traffic (a NFS connection). Where can I learn how to deal with these alerts? How can I suppress false-positives like these? I can find a truckload of information online about installation of Snort. But where to find information on the usage? Am I overlooking something? Any help will gladly be appreciated! Regards, Paul ----------------------------------------------------------------------- ------- Check out the vibrant tech community on one of the world's most engaging tech sites, Slashdot.org! http://sdm.link/slashdot _______________________________________________ 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://sourceforge.net/mailarchive/forum.php?forum_name=snort-users Please visit http://blog.snort.org to stay current on all the latest Snort news!
------------------------------------------------------------------------------ Check out the vibrant tech community on one of the world's most engaging tech sites, Slashdot.org! http://sdm.link/slashdot _______________________________________________ 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://sourceforge.net/mailarchive/forum.php?forum_name=snort-users Please visit http://blog.snort.org to stay current on all the latest Snort news!
Current thread:
- Starting off now it's running Paul Guijt (Apr 15)
- Re: Starting off now it's running Al Lewis (allewi) (Apr 15)
- Re: Starting off now it's running paul . guijt (Apr 16)
- Re: Starting off now it's running Al Lewis (allewi) (Apr 15)