RE: Concepts: Security and Obscurity

["Craig Wright" <Craig.Wright () bdo com au>]

1 Then there is an additional hazard function. The risk increases due to this possibility. The offset is a proposed 
increase in overall security. Studies from Vaos & Miller as well as others have modeled the hazard functions for 
software and this is a quantifiable area. The probability of a successful attack and the discovery of a vulnerability 
may be modeled on a number of factors which increase or decrease the condifence of the resultant function.
 
However, I have as yet seen nothing to show that obscurity adds any real quantifiable value to offset the loss from the 
software minimum time to hazard and mean time to hazard functions or even to cover the cost of managing a non-standard 
implementation.
 
2 Port knocking is reliant on a set secret that is replicated to a number of hosts/clients, is discoverable and relys 
on the secrecy of the process. Secrecy of the process not being the same as "something you know" as it is shared and 
open to a select group at the least.
 
Regards,
Craig
 
J Voas and K Miller "Predicting softwares minimum time to hazard and mean time to hazard for rare input events In Proc 
of the Int Symp on Software Reliability Eng

J Voas C Michael and K Miller "Condently assessing a zero probability of software failure High Integrity Systems Journal



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________________________________


From: listbounce () securityfocus com on behalf of Pranay Kanwar
Sent: Wed 18/04/2007 12:22 AM
To: security-basics () securityfocus com
Subject: Re: Concepts: Security and Obscurity



This discussion has really got interesting, still i would
like to make the following points.

1. What if port knocking daemon is itself vulnerable ?, then
you create a another point of failure.

2. Also i am still unclear on the fact that is using
a port knocking daemon would be really called obscurity ?.

Regards,
warl0ck // MSG
http://wwww.metaeye.org