[conspire] About conditioned helplessness

Luke S. Crawford lsc at prgmr.com
Fri Sep 2 10:16:14 PDT 2011


On Wed, Aug 31, 2011 at 08:06:08PM -0700, Rick Moen wrote:
> I had just gotten through sending her this summary of
> http://www.wired.com/threatlevel/2011/08/how-rsa-got-hacked/ :
> 
>   A major security company (RSA Data Security) had some of its crown-jewel
>   corporate secrets stolen recently.  How?  One of its engineers was
>   reading e-mail, and had Adobe Flash _including_ the ActiveX Flash
>   plugin for MSIE installed.  He encountered a mail with an Excel
>   spreadsheet attached.  He clicked the spreadsheet, which opened Excel,
>   which decided to open the ActiveX-enabled Flash interpreter to run a
>   Flash animation inside the spreadsheet.  Because ActiveX is horribly
>   overpowered and dangerous, _and_ because he was logged in with local
>   Administrator privilege, malware and a backdoor got installed and run by
>   Flash, which then stole corporate information and sent it to criminals.


this problem of a authorized user's workstation getting compromised
is a very difficult one to solve.   I think a lot about it myself, and
there is really no good way to protect the company from that situation
(you can make it harder for the attacker, e.g. by requiring a smartcard
that requires a pin or the like)  but if a admin logs in from a compromised
box, there really isn't much you can do to protect yourself from a 
sufficiently advanced attacker piggybacking on the legitimate connection.

Now, I think, RSA made an absolutely boneheaded mistake that changed
the breakin, in their case, from being an embarrassing sidenote to
it meaning that all their customers were also vulnerable to compromise.

They use shared secrets for authentication.

Those time-based tokens?  the seed is essentially a shared secret, and 
while they provide a secure way of transmitting that secret, I believe both 
ends need to know the secret.  This means that if the attacker compromises 
the server being authenticated to, in this case, an RSA owned server, the 
attacker can then use those secrets to attack other servers using the same 
authentication keys.

This is different from a public key system.  If the RSA tokens were proper
public-key tokens where the private key is generated on and never leaves 
the token?  the RSA compromise would only have netted the attacker a bunch 
of public keys;  which are much less useful when cracking a system.

So personally, I see this as a big warning against using shared-secret
auth, even if you do have a clever and secure way to transmit that shared
secret.

It's also reasonable to say the problem was that RSA kept the auth details
of all it's tokens.  If RSA only kept the auth details of each token on the
customer server(s) that those tokens needed to authenticate to, the problem
would have been largely mitigated anyhow.   I Mean, if you compromise
an authentication server, usually you can compromise the boxes that server
authenticates for regardless of the type of authentication used.  

-- 
Luke S. Crawford
http://prgmr.com/xen/         -   Hosting for the technically adept
http://nostarch.com/xen.htm   -   We don't assume you are stupid.  




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