Bugtraq: Re: Snort-inline

[Federico Petronio <petrus () activesec biz>]

Federico Petronio wrote:

> I have snort-inline 2.0.1 installed. I change the rule 2077 acction to 
> drop.
> Then I try to access, using Mozilla 1.5 and IE6.0, the URL:
> http://server_name/admin/fileman/upload.php?dir=
>
> the snort-inline log start showing lines like this:
>
> [**] [1:2077:2] WEB-PHP Mambo upload.php access [**]
> [Classification: access to a potentially vulnerable web application] 
> [Priority: 2]
> 01/13-18:31:06.944124 200.43.81.205:1586 -> 10.2.0.10:80 TCP TTL:117 
> TOS:0x0 ID:3095 IpLen:20 DgmLen:578 DF
> ***AP*** Seq: 0x45A19C2C Ack: 0x425899A4 Win: 0xFFFF TcpLen: 20
> [Xref => http://www.securityfocus.com/bid/6572]
>
>
> but after 5 minutes of that, the webserver finally got the query and 
> answed. That means that snort-inline let pass through the packet that 
> should drop. Can anyone check that? I try several time and got the same 
> result.
I reported this some time ago, and was not just about rule 2077 failing, 
but about all rules having the same problem. I search a little more and 
sent a couple of mails to the snort-inline list and finally found 
(thanks to Pieter Claassen) that the problem was that I set stream4 
preprocessor in the config file but that preprocessor is currently not 
supported by snort-inline.
When I commented the lines about stream4 the problem disappeared.

Regards,
--
                                        Federico Petronio
                                        petrus () activesec biz