RE: Finally - Curphey award 2004 to SPI Dynamics

["Sebastien Deleersnyder" <sdl () ascure com>]

Hi,

A bit late, but I am going through a pile of mail myself, and kicking in
an open door:

The problem with this kind of application level firewalls is that it can
protect you agains most common input validation mistakes, but when it
comes to design mistakes they will fail and only provide a false sense
of security (like the 'old' firewall story).
We should not fall in this trap a 2nd time: A have an (Application
Level) Firewall thus I should feel safe?
An application level firewall can provide defense in depth, but should
not replace proper security design/implementation throughout the whole
SDLC.

Kind regards,

Sebastien




-----Original Message-----
From: Madsen, Villy [mailto:Villy.Madsen () atcoitek com] 
Sent: dinsdag 29 juni 2004 16:19
To: Mads Rasmussen; Mark Curphey
Cc: webappsec () securityfocus com; Jeff Williams
Subject: RE: Finally - Curphey award 2004 to SPI Dynamics

While I do not advocate that Developers be allowed to get lazy about
security,

I also feel that providing a standard tool that they can use to filter
input is a bad thing.

Way back a couple of decades ago, I was involved in a Telco project to
rewrite an application used by Long Distance Telephone operators to
manage "Time and Charges" calls.   The application was finally shut down
in 2000.

One of the "breakthroughs" that we pioneered was the heavy use of what
was we called Table Driven IO.  All data input or output from the system
was defined by a set of mapping tables, that defined what the data could
look like, how long it was, and where it was mapped to in the
application data schema. 

The "mapping" applications were general purpose, checked for proper type
- performing whatever data conversions where necessary, guarded against
overflows etc etc.

Sounds very similar to me.

I thought it was a great idea then, and I still do...

One application to vet (the mapping routine), and a bunch of tables to
validate.

Easier than validating all of the code snippets that are "accepting
Input" from the external world....


Villy


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-----Original Message-----
From: Mads Rasmussen [mailto:mads () opencs com br]
Sent: Tuesday, June 29, 2004 5:47 AM
To: Mark Curphey
Cc: webappsec () securityfocus com; Jeff Williams
Subject: Re: Finally - Curphey award 2004 to SPI Dynamics


Mark Curphey wrote:
> Here I am, depressed at the prospect of filling in mountains of 
> expense claims from weeks of traveling and approving mundane mails to 
> webappsec about XSS after XSS and along comes a shining light. At last

> an "application security" company that gets it ! Hats of to the folks 
> at SPI and the Curphey Award for 2004 for leading the industry down 
> the right path !
>
> http://biz.yahoo.com/prnews/040628/clm006_1.html

Here is another link http://www.eweek.com/article2/0,1759,1617901,00.asp

I don't know about you guys but I have a bad feeling about this. I am 
not sure this is the right path.

The article quotes Caleb Sima, founder and chief technology officer of 
SPI Dynamics saying "It doesn't require developers to learn about 
security," - "You really just need to validate input to eliminate most 
application vulnerabilities."

Shouldn't you at least have a feeling for where the developers makes 
their mistakes to be able to insert the right piece of secure code?

By all means it looks like a cool product, but how much can we trust it?

One of its features is, qoute
"Input Validation objects will check incoming data on web forms to
validate user-supplied input against a set of rules and prevent
parameter manipulation exploits, such as SQL Injection attacks."

Can we trust these "set of rules".
If they opened their technology, the OWASP team could contribute rules 
to such a database and then we just might get somewhere by having a list

of f.ex regular expressions for using the validator classes in .Net or 
input validation in general but that would probably not happen.

I am concerned that products like this just leads to lazy developers.

Jeff what do you think about this? You wanted to start an input 
validation project based on filters, a database like described above 
would be quite handy :o)

Just my two bits

-- 
Mads Rasmussen, M.Sc.
Open Communications Security
www.opencs.com.br
+55 11 3345 2525