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RE: Checkpoint smart defance as IPS
From: "Craig S. Wright" <craig.wright () Information-Defense com>
Date: Sat, 5 Jun 2010 07:01:12 +1000

"security is to increase difficulty level for an attack."
BS.

So If I go from 60 seconds to average compromise to 90 seconds, I am secure?
By your analysis this is the case.

Security is a function of survivability, continuity and reliability.

Perception of security can add to security if it deters malicious action.
This is not security in itself. Security is a risk function 

"So difficulty involved in registering an RA is part of the security of
PKI."
No, it is a part of the bureaucracy. The chain of trust and the fact that
you can validate which certificate was used is. As noted in prior posts,
this is flawed. There are several CAs still using MD2 and with valid MD5
root certs. On top of this there are looming issues with SHA1. Strange as it
seems, it is simpler and less hassle to create and sign a false certificate
than to go through all of the paperwork etc to become a CA. The create your
own without authority option is illegal. 

The fact that criminal groups break the law means that they do opt for the
illegal option. This means that their certificates are NOT a part of the
valid repudiation chain. You can forensically determine that the end user
was issued a fraudulent cert, but not the parties it went to etc.

There is a wide chasm between the use of an internally trusted root cross
signed RA within an organisation and the interception of Internet traffic
for illicit financial gain. Anyone who cannot see this difference has a
problem. It is also not of much use for an organisation to do this. The
cross signing process means that their certificate is signed and publically
available. They are responsible for any fraud conducted using it (hence the
insurance requirement from most CAs who cross sign).

Simple answer, can a CA be configured that can issue certs via Checkpoint
... Yes. Will this enable SSL reverse proxies without client warnings?

Yes, the internal cross signed RA certifies the CP self signed cert or the
one issued in the hierarchy. There are CP documents on this process.
CheckPoint is finicky and necessitates that chained CA certificates contain
the full FQDN chain in the intermediate certificate. So getting the
certificate chain right is essential. All of the other caveats re
configuring a cross singed and chained CA apply.

As a side note, the SHA-1 signing algorithm has problems as well. It is a
little more difficult to exploit than MD5, but not outside the reach of many
illicit groups.

Regards,
...
Dr. Craig S Wright GSE-Malware, GSE-Compliance, LLM, & ...
Information Defense Pty Ltd



-----Original Message-----
From: Shreyas Zare [mailto:shreyas () secfence com] 
Sent: Saturday, 5 June 2010 12:55 AM
To: craig.wright () information-defense com
Cc: security-basics () securityfocus com
Subject: Re: Checkpoint smart defance as IPS

Hi Craig,

What a great BS idea! So in the context of this thread, you want
organizations to setup their own RA and illegally fake all the SSL
certificates? IANAL but this is still an infeasible solution. Also, do
you regularly sell illegal solutions to your clients like this?

And for the challenge part, you want me to pay for setting up RA which
will be used basically to fake certificates and is totally not legal
and out of question?

You are forgetting the purpose of security. While all complex systems
can be compromised in some way at some level, security is to increase
difficulty level for an attack. So difficulty involved in registering
an RA is part of the security of PKI. And as you know, the entire PKI
system works on trust factor, your solution for the current thread
scenario is invalid and thus your claim is invalid. Nothing is broken
in here; the system is working as it was designed. SSL/TLS and PKI are
working as designed and serving the purpose for which they were
designed for - provide privacy, authentication and protect against
MITM.

All this stupid argument was done because of out of context claims and
shear stupidity on your part which any sane person reading this list
would agree too. And then your arguments are filled with stupid things
that don't really explain your claim in the context of the thread.

I too can claim (for fun ofcourse!) that I have capability to
intercept *any* SSL/TLS communication in the world, only I need to
takeover Verisign! Those who want to challenge must take over Verisign
first hand over it to me! So simple, isnt it?! (Terms and Restrictions
apply!)

The challenge experiment is still open if you don't ask for infeasible
requirements and have some other techniques to accomplish the task at
your disposal (don't ask me to deliver 200 PS3 processors to
Australia!).

Regards,

Shreyas Zare

Sr. Information Security Researcher
Secfence Technologies
www.secfence.com

“Two things are infinite: the universe and human stupidity; and I'm
not sure about the the universe.” - Albert Einstein


On Fri, Jun 4, 2010 at 12:40 PM, Craig S. Wright
<craig.wright () information-defense com> wrote:
You pay the costs and no problem.

Co9sts are for an RA setup. Not my clients ones, but you arrange to pay
the
costs for this and I will happily do it.

Regards,
...
Dr. Craig S Wright GSE-Malware, GSE-Compliance, LLM, & ...
Information Defense Pty Ltd



-----Original Message-----
From: Shreyas Zare [mailto:shreyas () secfence com]
Sent: Friday, 4 June 2010 5:02 PM
To: craig.wright () information-defense com
Cc: security-basics () securityfocus com
Subject: Re: Checkpoint smart defance as IPS

Hi Craig,

If you still claim its possible, why not you take this challenge? The
challenge is quite clear and "easy" to achieve for you. It will prove
the point and enlighten us all on the list. We would fix a favorable
date and time (UTC) and do it. What you say?

And since you are stressing on the MD5 collision point, the researcher
took a weeks time to create a fake cert using 200 PS3 Cell Processor.
While that was really impressive and can be practical too for a
particular target; its not what you claim. You claim your system works
on-the-fly for any website.

Challenge quoted below again for clarity:

==BEGIN CHALLENGE==
1. I, with my personal laptop will connect to any VPN that you provide.

2. I would use my default web browser (Firefox v3.6.3 with no-script
addon) and would visit *any* HTTPS website I wish and login with my
credentials.

3. This VPN that I would dial, can/will be in your control; you can
route the traffic anyway to the internet (this part is quite easy to
achieve) and sniff the data and do whatever you can do to intercept
and "decrypt" the traffic.

4. I will use the DNS server which the VPN connection provided.

5. I would visit only one website, login then disconnect the VPN.
There will be only one attempt for me to login to that website. I
would myself capture the traffic that went through VPN with wireshark
for comparison and post it.

6. You would then use whatever means possible to get my credentials
and you can freely post it publicly on the list or on any other forum.

7. And since, as you claim, this will happen on-the-fly, you will have
to post the credentials within 24hrs on the list (24hrs is too
generous anyways).
==END CHALLENGE==

Regards,

Shreyas Zare

Sr. Information Security Researcher
Secfence Technologies
www.secfence.com


On Fri, Jun 4, 2010 at 2:55 AM, Craig S. Wright
<craig.wright () information-defense com> wrote:

As stated, yes this is possible.

As I have also stated, the browser trusts all certificate authorities
equally. There is evidence of the change. The repudiation features of
certificates allow you to have a copy that proves I was in the middle. To
do
this, you have to check certificate finger-prints for the most part.

All traffic from your site is redirected via a controlled gateway. Unless
you have been to a website before, you will have no idea of any change at
all. There is no single root CA, there are 100's of them. If you have
been
to a site before, it will depend on your browser settings. Firefox will
alert the change in CA is a CA from a different country is used. IE can
be
configured to do something similar (both if you have the latest version
IE
7
does not do this and nor does an older version of Firefox).

I have a cross signed root certificate. As an enterprise with at least
$5million in assets etc, it is not too difficult to obtain. There are at
least 80 CAs that will issue one. Some are easier and require far less
validation. A savvy user may think it is strange that it is strange that
the
US government uses a CA in China, but few non-IT (and even most IT)
people
do not check.

I issue a zero key from my RA. This is self signed. The self signed cert
is
trusted as a cross signed CA has trusted the signing cert. As the browser
has a list of root CA's it trusts, my chained cert is also trusted.

This is if I am doing this honestly. I could also spoof a request to a
CA.
http://www.phreedom.org/research/rogue-ca/md5-collisions-1.0.ppt

MANY CAs still have predictable serial #s. Some are low volume making
this
simple if you are willing to spend the money (about $1-5k). Many still
take
ASCII Nulls in submissions. Worse, there are several CAs that take
submissions through a browser correctly, but which can be spoofed with
the
standard injection techniques to accept non-ASCII chars. Many Asian CAs
will
take "funky" characters, making other attacks possible.

Several CAs still have MD5 if you know where to go. There are also issues
with SHA1, but I will not go into this here...

Google's cert fingerprint has changed several times this year. Ebays a
few
as well. Have you called them to manually validate the certificate? If
not,
then you can be MiTM'd.

Do you write down the cert fingerprint for your online banking? Do you
check
it each time and call the bank if it changes?

"X.509 is a remarkably fragile piece of work." Dan Kaminsky, 2009.

Regards,
...
Dr. Craig S Wright GSE-Malware, GSE-Compliance, LLM, & ...
Information Defense Pty Ltd



-----Original Message-----
From: Shreyas Zare [mailto:shreyas () secfence com]
Sent: Friday, 4 June 2010 2:30 AM
To: craig.wright () information-defense com
Cc: security-basics () securityfocus com
Subject: Re: Checkpoint smart defance as IPS

Hi Craig,

I dont know whats missing, may be the issue is not clear. I will write
the claim you made in below paragraph:

You claim that its possible to Man In The Middle (MITM) attack on
*any* SSL/TLS communication without tampering anything on the client
side and that SSL/TLS is, and can, be intercepted for *any* possible
website a client visits on-the-fly.

Now, I will create a scenario which will make things clear:

1. I, with my personal laptop will connect to any VPN that you provide.

2. I would use my default web browser (Firefox v3.6.3 with no-script
addon) and would visit *any* HTTPS website I wish and login with my
credentials.

3. This VPN that I would dial, can/will be in your control; you can
route the traffic anyway to the internet (this part is quite easy to
achieve) and sniff the data and do whatever you can do to intercept
and "decrypt" the traffic.

4. I will use the DNS server which the VPN connection provided.

5. I would visit only one website, login then disconnect the VPN.
There will be only one attempt for me to login to that website. I
would myself capture the traffic that went through VPN with wireshark
for comparison and post it.

6. You would then use whatever means possible to get my credentials
and you can freely post it publicly on the list or on any other forum.

7. And since, as you claim, this will happen on-the-fly, you will have
to post the credentials within 24hrs on the list (24hrs is too
generous anyways).


This exercise would clear up things that you claim and surely the
entire mailing list would like to know how this thing is really
technically possible and how you achieved it.

Regards,


Shreyas Zare

Sr. Information Security Researcher
Secfence Technologies
www.secfence.com




On Thu, Jun 3, 2010 at 1:08 PM, Craig S. Wright
<craig.wright () information-defense com> wrote:
"DNSSEC is not related to SSL/TLS security"
SSL security is based on DNS. DNSSEC is security for DNS.

" Again I would say my point: you *cannot* do MITM on a website if you
don't
have private key for the certificate on that website."
Really? I have devices doing this at clients right now.

" If you are NSA, you can crack the encryption with brute force and
that
too
will take quite some time."
BS

"Again for god sake, this is social engineering! there is no way this
can be used to MITM an existing SSL website. Well, if you can get a
cert from any of the 264+ CA for citibank, that would be fault of the
CA and not SSL/TLS or PKI, plus that would involve legalities. This
compromise is in theory possible, but again you need access to a CA
and SSL/TLS protocol is still not broken (its working as designed)"

No it is not, the certs are already in the browser. I can get a .com
cert
from several CAs.

" not possible for any guy to obtain the same "
Really? I have setup a number of RAs.

" Lastly, why on earth would people use electronic banking if what you
claim is true and so easy to carry out?"

As the issue is not one people care about. The banks have the risk. DNS
and
routing are the weak points. Perception.

Well the simple thing here is I do this for clients from time to time.
I
am
happy to know I am doing the impossible.

Encrypted is NOT secure. It is private. These are not the same thing.
If
you
actually believe that SSL is security, then I feel sorry for your
clients.

Regards,
...
Dr. Craig S Wright GSE-Malware, GSE-Compliance, LLM, & ...
Information Defense Pty Ltd



-----Original Message-----
From: Shreyas Zare [mailto:shreyas () secfence com]
Sent: Thursday, 3 June 2010 4:56 PM
To: craig.wright () information-defense com
Cc: security-basics () securityfocus com
Subject: Re: Checkpoint smart defance as IPS

Hi Craig,

I disagree with you my friend. And the points you are using to defend
your previous claim are totally different and thus not valid for the
argument.

Firstly, you claim that SSL/TLS can be intercepted and MITM is
possible (and effectively protocol is broken). And now you defend it
citing bad implementation of SSL/TLS in browsers and social
engineering. Most of your points (like phishing, fake domains etc) are
social engineering and not MITM or interception for that matter.

SSL/TLS is not to protect user from his/her stupidity. SSL/TLS do
provide a secure channel to a site and you cannot just sniff the
traffic and decrypt it (as you suggest).

DNSSEC is not related to SSL/TLS security. Clients just blindly trust
their ISP DNS server. DNSSEC is to make faking/spoofing a DNS reply
really difficult and it will be done using digital signatures. And
surely, you can attack DNSSEC too with social engineering or making
the client machine trust a fake CA that you control then sign a fake
reply with your private key.

Again I would say my point: you *cannot* do MITM on a website if you
don't have private key for the certificate on that website. However,
you can be a CA and fake a certificate on the fly on your gateway,
that too only when the client trusts the CA in the first place. If you
are NSA, you can crack the encryption with brute force and that too
will take quite some time.

And ...

On Thu, Jun 3, 2010 at 4:45 AM, Craig S. Wright
<craig.wright () information-defense com> wrote:
Hello,
I suggest that you learn to reference more than simply Wiki.

I suggested you wiki to get the basics. and wikipedia for that matter
is really good. You claimed that browser only checks for domain name
and totally didn't know about the handshake which involves private key
of the website.



"If it was possible as you claimed, the protocol will be totally
broken
and
it will be front page news article."
I suggest you keep up. This is why TLS was introduced (which also has
flaws)
- which is still not used correctly either. But read on for something
that
matters.




http://blog.washingtonpost.com/securityfix/2006/02/the_new_face_of_phishing_
1.html


Phishing is not MITM, its social engineering.



PS. A complete compromise of the CAs and DNS would not likely make a
front
page article. Most people do not care and it is not something that
sells
papers.

A persons net-banking account can be intercepted while he and his bank
wont care? great!



This is also why DNS and routing are important. What do you think
DNSSEC
is
really about?

DNSSEC and SSL/TLS are different things. SSL/TLS use certificates to
match domain that's true but, the handshake is done as client sends a
random number encrypted with public key and the server which has the
private key can *only* decrypt it.




SSL is about privacy, NOT security. It was NEVER about security.

this is simply great!




How about I give you some real reading, something more than the online
golden book encyclopaedia that is Wikipedia...

Thanks, I have done much more reading already.




Let's take a quote from Kurt Seifried:
"Even ignoring all these problems the simple fact is that SSL
certificates
only identify the server to the user, they do not authenticate it.
This
is
a
subtle but incredibly important difference. My online bank is at
tdbank.ca,
td.ca on the other hand is owned by someone else and banktd.ca is
still
free. I know for example that www.openssl.org is the "official" site
for
OpenSSL, but what about www.openssl.de? Shouldn't that be the official
site
for OpenSSL translated into German? Well it turns out that it isn't.
Do
you
trust every single root certificate in your webbrowser software? Have
you
even heard of "IPS SERVIDORES" (ips.es), "Saunalahden Serveri CA"
(saunalahti.fi) or "SERVICIOS DE CERTIFICACION - A.N.C."
(correo.com.uy)?
I
sure as heck haven't."

REMEMBER - ALL CERTIFICATE AUTHORITIES ARE EQUALLY
TRUSTED!!!!!!!!!!!!!!!!

I have to state this again...

ALL CERTIFICATE AUTHORITIES ARE EQUALLY TRUSTED!!!!!!!!!!!!!!!!

Do you think your users go and check the CA and ensure it is really
the
one
that the real site has used? If you think users do this, you have some
learning to do.

If you actually believe that you cannot obtain a signed (from a CA in
IE's
list) certificate for a MiTM device, you have not looked too hard.

If you do not think this is a known issue, try reading some RFC's:
"[Browser vendors] and users must be careful when deciding which
certificate
and certificate authorities are acceptable; a dishonest certificate
authority can do tremendous damage."
RFC 2246, The TLS Protocol 1.0

The 264+ root CAs trusted by Microsoft, the 166 root CAs trusted by
Apple,
and the 144 root CAs trusted by Firefox are capable of issuing
certificates
for any website, in any country or top level domain.
See Ed Felten. "Web Certification Fail: Bad Assumptions Lead to Bad
Technology". Freedom To Tinker, February 23 2010.




www.freedom-to-tinker.com/blog/felten/web-certification-fail-bad-assumptions
-lead-bad-technology.


Again for god sake, this is social engineering! there is no way this
can be used to MITM an existing SSL website. Well, if you can get a
cert from any of the 264+ CA for citibank, that would be fault of the
CA and not SSL/TLS or PKI, plus that would involve legalities. This
compromise is in theory possible, but again you need access to a CA
and SSL/TLS protocol is still not broken (its working as designed)




Next, "'Packet Forensics' devices are designed to be inserted-into and
removed-from busy networks without causing any noticeable interruption
[.
.
. ] This allows you to conditionally intercept web, e-mail, VoIP and
other
traffic at-will, even while it remains protected inside an encrypted
tunnel
on the wire. Using `man-in-the-middle' to intercept TLS or SSL is
essentially an attack against the underlying Diffie-Hellman
cryptographic
key agreement protocol [. . . ]".
Packet Forensics. Export and Re-Export Requirements, 2009.
www.packetforensics.com/export.safe.

So - the question is... have you removed all but the "trusted" CA's
from
your users browsers? I doubt it. If you have, you also need to do this
EACH
and EVERY time that IE updates.

Again you need access to a CA, which a government like US can do for
sure. And its again not possible for any guy to obtain the same.




Next, have a read of more than this forum. Try the TLS list from the
IETF:
http://www.ietf.org/mail-archive/web/tls/current/msg03928.html

From the link:
"The problem:  when Microsoft IIS is configured to request a client
certificate after having received the request, then it WILL perform
an unauthenticated request!  Sending the reply back only to the
authenticated client is a poor excuse for acting on an unauthenticated
request."

That is bad implementation of SSL, isn't it? and that too specific to
a particular server. And in normal HTTPS scenario, client don't send a
cert to server.




Even not paying for a certificate (which is the option for the
scenario
this
derived from), you can still attack SSL/TLS:
"...inject a chosen plaintext prefix into the encrypted data stream,
often
without detection by either end of the connection. This is possible
because
an "authentication gap" exists during the renegotiation process at
which
the
MitM may splice together disparate TLS connections in a completely
standards-compliant way."
See




http://extendedsubset.com/wp-uploads/2009/11/renegotiating_tls_20091104_pub.
zip

Finally, have you ever thought of a zero bit negotiated key. SSL with
0-bit
encryption. This can be done using a 128 bit certificate. The client
to
the
IPS is clear text, but looks to the browser as being encrypted.


Again an example of bad implementation in application.




Research means more than wiki. If you use a title of researcher, it is
something that you should try to do.

Thanks for the tip. But, one really needs to read basics first not
matter from wiki or some another source.



Regards,
...
Dr. Craig S Wright GSE-Malware, GSE-Compliance, LLM, & ...
Information Defense Pty Ltd



Lastly, why on earth would people use electronic banking if what you
claim is true and so easy to carry out? While there are many attacks
possible in theory, implementing them practically is very difficult
indeed. And such attack will depend on bad implementation issues or
social engineering. Still, doing a attack based on social engineering
is quite viable option but, the success rate of such attack would vary
with the target population.


Regards,

Shreyas Zare

Sr. Information Security Researcher
Secfence Technologies
www.secfence.com






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