Re: Enquiry on PCRE

[yew chuan Ong <yewchuan_23 () yahoo com>]

Why it is anything EXCEPT a ":" or a "?"? Where is the keyword? =)


________________________________
 From: Alex Kirk <akirk () sourcefire com>
To: yew chuan Ong <yewchuan_23 () yahoo com> 
Cc: "snort-sigs () lists sourceforge net" <snort-sigs () lists sourceforge net> 
Sent: Wednesday, June 20, 2012 7:12 PM
Subject: Re: [Snort-sigs] Enquiry on PCRE
 

It's anything except a ":" or a "?", 11 or more times, followed by ":/". Note that the whole thing is anchored to the 
start of the URL by the leading "^".


On Tue, Jun 19, 2012 at 11:08 PM, yew chuan Ong <yewchuan_23 () yahoo com> wrote:

Hi Guys,
> I am kind of confuse with the pcre in this rule:
> pcre:"/^[^\x3a\x3f]{11,}\x3a\x2f/Usmi"
>
>
> alert tcp $EXTERNAL_NET any -> $HTTP_SERVERS $HTTP_PORTS (msg:"WEB-MISC Checkpoint Firewall-1 HTTP parsing format 
> string vulnerability attempt"; flow:to_server,established; content:"|3A|/"; offset:11; http_uri; 
> pcre:"/^[^\x3a\x3f]{11,}\x3a\x2f/Usmi"; reference:bugtraq,9581; reference:cve,2004-0039; reference:nessus,12084; 
> classtype:attempted-admin; sid:2381; rev:15;) 
>
>
> Does it mean that the payload should have ":?" appeared for at least 11 times and following with ":/"?
> Thanks!
>
>
>
>
> RegardsYC
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-- 
Alex Kirk
AEGIS Program Lead
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alex.kirk () sourcefire com

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Exclusive live event will cover all the ways today's security and 
threat landscape has changed and how IT managers can respond. Discussions 
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