Snort mailing list archives
Re: Rules with options like http_uri of flow
From: Nicholas Mavis <nmavis () sourcefire com>
Date: Tue, 17 Dec 2013 16:56:52 -0500
Onno, The http_uri option will not work with the content match you've created as GET is not within the http_uri buffer. The HTTP method would be in the http_method buffer. As for flow established, how are you testing this rule? Is there a full tcp handshake seen before the GET request? I was able to get this rule to alert with both options, here is the rule I created: alert tcp any any -> any $HTTP_PORTS (msg:"WEBSERVER - test rule blaat.txt"; flow:to_server,established; content:"/blaat.txt"; nocase; http_uri; metadata:service http; classtype:web-application-attack; sid:1000100; rev:18;) -Nick Mavis On Tue, Dec 17, 2013 at 4:11 PM, rmkml <rmkml () yahoo fr> wrote:
Hi Onno, Could you check when disable cksum verification please ? (-k none) Regards @Rmkml On Tue, 17 Dec 2013, onno () b00z nl wrote:Hi, I've some, at least for me, weird behaviour with snort rules. I already reinstalled every thing 3 times, but still haven't it to work. The sensor is passive and connected to a switch monitor port. I'm testing the setup for monitoring both in- and outbound traffic, so I configured both HOME_NET and EXTERNAL_NET with any. While I was testing, I discovered that I was unable to fire some rules. So I created the following test rules: This one is working when requesting an URL like http://<hostname>/blaat.txt alert tcp $EXTERNAL_NET any -> $HTTP_SERVERS $HTTP_PORTS (msg:"WEBSERVER - test rule blaat.txt"; content:"GET /blaat.txt"; nocase; metadata:ruleset community, service http; classtype:web-application-attack; sid:1002; rev:18;) This rule is derived from an existing one. But the modified existing one has also the following options: flow:to_server,established; and/or http_uri; But as soon as I add one of those options, the rule won't fire. And because of that I think that there might be something wrong with my setup and that it won't hit on other rules also. This is an example of a rule that won't fire: alert tcp $EXTERNAL_NET any -> $HTTP_SERVERS $HTTP_PORTS (msg:"WEBSERVER - test rule blaat.txt"; flow:to_server,established; content:"GET /blaat.txt"; nocase; metadata:ruleset community, service http; classtype:web-application-attack; sid:1002; rev:18;) Even without the flow option and with http_uri, it does not work. Any insight would be great. Thanks! Onno.------------------------------------------------------------------------------ Rapidly troubleshoot problems before they affect your business. Most IT organizations don't have a clear picture of how application performance affects their revenue. With AppDynamics, you get 100% visibility into your Java,.NET, & PHP application. Start your 15-day FREE TRIAL of AppDynamics Pro! http://pubads.g.doubleclick.net/gampad/clk?id=84349831&iu=/4140/ostg.clktrk _______________________________________________ Snort-sigs mailing list Snort-sigs () lists sourceforge net https://lists.sourceforge.net/lists/listinfo/snort-sigs http://www.snort.org Please visit http://blog.snort.org for the latest news about Snort!
------------------------------------------------------------------------------ Rapidly troubleshoot problems before they affect your business. Most IT organizations don't have a clear picture of how application performance affects their revenue. With AppDynamics, you get 100% visibility into your Java,.NET, & PHP application. Start your 15-day FREE TRIAL of AppDynamics Pro! http://pubads.g.doubleclick.net/gampad/clk?id=84349831&iu=/4140/ostg.clktrk _______________________________________________ Snort-sigs mailing list Snort-sigs () lists sourceforge net https://lists.sourceforge.net/lists/listinfo/snort-sigs http://www.snort.org Please visit http://blog.snort.org for the latest news about Snort!
Current thread:
- Rules with options like http_uri of flow onno (Dec 17)
- Re: Rules with options like http_uri of flow rmkml (Dec 17)
- Re: Rules with options like http_uri of flow Nicholas Mavis (Dec 17)
- <Possible follow-ups>
- Re: Rules with options like http_uri of flow Onno van der Leun (Dec 18)
- Re: Rules with options like http_uri of flow Joel Esler (jesler) (Dec 18)
- Re: Rules with options like http_uri of flow Onno van der Leun (Dec 18)
- Re: Rules with options like http_uri of flow Joel Esler (jesler) (Dec 18)
- Re: Rules with options like http_uri of flow rmkml (Dec 17)