Subject: RE: Client-side revocation checking capability

From: "Morrill, Dan" <[email-masked]>
Date: Mon, 14 Aug 2000 13:09:50 -0700

Dennis,

My question then is, has anyone ever had a CA compromised? (not that it
could not happen, but usually CA's are on the "Must Secure at all costs"
level) Wouldn't that compromise be part of a policy statement? With
appropriate protocols to address a security issue.

I know that with the CA's that I have worked on, all of them are geared high
(Paranoid) on a sensor like Real Secure, with NetRanger and some Enterprise
management backup, so that if it goes red (looks like it is under attack),
the system is cut off the net whenever there is a possible breach, then the
folks are paged to come take a look. Normal response times, metrics and
other ways of reporting data then take over. If warranted, backups, disaster
recovery protocols then go into effect. Then there is network issues that
can go a long way to secure a CA from compromise. 

I think that security of a CA is more policy than is a technical
specification. Feel free to disagree.
R/
Dan Morrill
Computer Sciences Corporation

-----Original Message-----
From: Dennis Glatting [mailto:[email-masked]]
Sent: Monday, August 14, 2000 01:02 PM
To: Anders Rundgren
Cc: Bob Jueneman; [email-masked]; [email-masked]
Subject: Re: Client-side revocation checking capability

Anders Rundgren wrote:

> To get a new server-certificate is BTW not that trivial so it makes sense
to improve
> local security in various ways.
> 

One of the (many) problems with the PKI as it is today (okay, SSL/TLS)
is all you need is to compromise one CA and you can issue bogus server
certificates and set up bogus web sites to your hearts content, at
least for a while. The popular browsers have many root certificates,
58 in Netscape I believe. If you compromise one of those roots then a
browser is going to accept a certificate from a compromised CA with
Amazon.COM and DNS spoofed without distinction from the real
Amazon.COM. Another trick is to send a viral laden e-mail message to
the masses and implant a root certificate. 

In both cases I am skeptical of the value of CR. I am also skeptical
that all consumers would repair their systems even with a flood of
strongly worded advertising. So, :), I believe a compromised or
spoofed (bogus embeded root certificate) root is the kind of gift that
keeps on giving.

---

From: Dennis Glatting <[email-masked]>
Date: Mon, 14 Aug 2000 13:53:04 -0700

> appropriate protocols to address a security issue.

I have not heard of any CA compromise.

> specification. Feel free to disagree.

Of course CAs can be compromised, web sites spoofed, implementations
be of low caliber, and browsers and computers attacked in various
imaginative was. Some of these things are unlikely and others very
likely. All are possible and some aren't very hard. The overall point
of my comments is by checking CRLs we improve the quality of
transactions.

---

From: Al Arsenault <[email-masked]>
Date: Mon, 14 Aug 2000 21:12:03 -0400

This is getting kind of off-the-track of "checking whether or not user
certificates have been revoked", but...

Of equal interest to CA compromise is the case where the CA goes
bankrupt.  Then the CA's private key is in essence "compromised" by, for
example, being auctioned to the highest bidder.

It's analogous to the situation that happens all too often today where,
when a dot.com starts running into financial trouble, or actually goes
under, the customers' private information is sold to the highest bidder
or to many bidders to raise funds, pay off creditors, etc.

So the company with its public key embedded in IE and/or Netscape goes
belly-up.  In swoops "Joe's Storm Door and Network Security Company"
with a sweet financial bid for the private key, either directly or
through the bankruptcy court.  (That private key is an asset of the
company and can be disposed of in a manner that raises the most value
for the creditors.)  Once "JSD&NSC" has the private key, who knows what
kinds of certs get issued.  And since the public key is embedded in
millions of copies of the browsers, and can't easily be removed except
for millions of users doing it manually, or upgrading to the next
version of the browser that doesn't have that "trusted" root key
embedded in it, ... (I'll leave it to the reader to figure out what can
happen, to whom, and for how long.)

BTW:  this has already happened, in real life.  Apparently, the bids in
bankruptcy court for the private key started soaring to fairly high
levels, rather quickly.  Turned out to be just about the only marketable
asset the company had.

			Al Arsenault