Re: draft-zourzouvillys-sip-via-cookie-00

Hi Theo,

I was just thinking of a scenario,suppose the attacker creates a spoofed
invite,and inserts his ip in the Via header field and an empty cookie
parameter in the via header field.The Proxie which he wants to use as an
ampilfier in a DoS attack,on receiving such a request will respond with
a 4xx response,and the value of the cookie parameter to be used.On
receiving the cookie,the attacker,resends the invite with the cookie
value and deletes its entry from the Via header field.Thus now the
responses for this invite will be sent back to the UAC which is to be
the victim of the DoS attack only.The UAC which is attacked will receive
a minimum of 22 responses only.

What do you think about this.


Thanks and regards,
 
Shamik Saha
Project Engineer
Voice Protocols
Cell :  +91-9886704155

-----Original Message-----
From: [email protected] [mailto:[email protected]] On Behalf Of
Theo Zourzouvillys
Sent: Friday, February 20, 2009 9:50 AM
To: SIP WG
Subject: [Sip] draft-zourzouvillys-sip-via-cookie-00

Hi,

I've just submitted an ID that discusses the inherent UDP "problem",
along with a potential workaround to stop it being used maliciously.

I would really welcome any feedback:

 
http://www.ietf.org/internet-drafts/draft-zourzouvillys-sip-via-cookie-0
0.txt

 ~ Theo
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_______________________________________________
Sip mailing list  https://www.ietf.org/mailman/listinfo/sip
This list is for NEW development of the core SIP Protocol
Use [email protected] for questions on current sip
Use [email protected] for new developments on the application of sip