Snort mailing list archives
Re: Snort Timestamps Out of Sequence
From: "Joel Esler \(jesler\) via Snort-devel" <snort-devel () lists snort org>
Date: Wed, 17 Apr 2019 10:59:16 +0000
Is that “out of order” alert a reassembled pseudo-packet? You’d need to look at the packets in the alerts themselves to determine that. (Not csv, but you could look at something like “ -A cmg” to help diagnose this) Sent from my iPhone
On Apr 17, 2019, at 06:56, ROTNEMER, ALAN H via Snort-devel <snort-devel () lists snort org> wrote: We have run Snort where we send it packets that are in timestamp order. However, the alerts will occasionally come back out of sequence to our application. By turning on “output alert”, we can see from the log file that alerts can be delayed. For example, we ran snort as: /opt/capture/bin/snort -c /opt/capture/conf/snort/etc/snort.conf -i lo -S OUT_FILE=/data/working/snort/proc/99_99 -N -q & And in /opt/capture/conf/snort/etc/snort.conf we had the line: output alert_csv: /tmp/snortf1.csv timestamp,msg,src,srcport,dst,dstport The CSV log file had several instances similar to this (for business reasons the exact rule texts were redacted): 04/16-02:11:06.572717 ,"Rule Type 1 Protocol Outbound Traffic",154.45.216.145,1098,99.99.37.223,51413 04/16-02:11:06.606885 ,"Rule Type 1 Protocol Outbound Traffic",182.72.124.202,25283,108.228.86.35,6881 04/16-02:11:06.609897 ,"Rule Type 1 Protocol Outbound Traffic",94.254.163.20,19973,99.127.74.163,9836 04/16-02:11:06.615137 ,"Rule Type 1 Protocol Outbound Traffic",185.39.113.72,44143,75.35.93.63,6881 04/16-01:56:08.636576 ,"Another Rule2 #2",216.68.181.150,65381,12.96.144.101,80 04/16-02:11:06.667118 ,"Rule Type 1 Protocol Outbound Traffic",178.254.221.60,8073,99.138.149.126,52241 04/16-02:11:06.673093 ,"Rule Type 1 Protocol Outbound Traffic",196.64.27.94,16119,71.128.163.20,6881 04/16-02:11:06.676153 ,"Rule Type 3",61.220.63.0,6520,98.67.182.104,123 The alert for timestamp 01:56:08 appears 15 minutes behind the ones preceding it. The original packet has the correct timestamp. I should note that this is a very busy system with multiple packets per second being generated. The user-generated rules file has about 23,000 rules. Can I get an explanation as to how snort is processing individual packets going through the rules? I would expect to see the alerts come back in the same sequence they went in. Thank you for any assistance. If more information is needed please let me know. _______________________________________________ Snort-devel mailing list Snort-devel () lists snort org https://lists.snort.org/mailman/listinfo/snort-devel Please visit http://blog.snort.org for the latest news about Snort!
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Current thread:
- Snort Timestamps Out of Sequence ROTNEMER, ALAN H via Snort-devel (Apr 17)
- Re: Snort Timestamps Out of Sequence Joel Esler (jesler) via Snort-devel (Apr 17)
- Re: Snort Timestamps Out of Sequence ROTNEMER, ALAN H via Snort-devel (May 06)
- Re: Snort Timestamps Out of Sequence Joel Esler (jesler) via Snort-devel (May 06)
- Re: Snort Timestamps Out of Sequence ROTNEMER, ALAN H via Snort-devel (May 23)
- Re: Snort Timestamps Out of Sequence Joel Esler (jesler) via Snort-devel (May 23)
- Re: Snort Timestamps Out of Sequence ROTNEMER, ALAN H via Snort-devel (May 23)
- Re: Snort Timestamps Out of Sequence Russ via Snort-devel (May 25)
- Re: Snort Timestamps Out of Sequence ROTNEMER, ALAN H via Snort-devel (May 06)
- Re: Snort Timestamps Out of Sequence Joel Esler (jesler) via Snort-devel (Apr 17)