Re: [Cryptography] Protecting Private Keys

2013-09-08 Thread Peter Gutmann
Jeffrey I. Schiller j...@mit.edu writes:

If I was the NSA, I would be scavenging broken hardware from “interesting”
venues and purchasing computers for sale in interesting locations. I would be
particularly interested in stolen computers, as they have likely not been
wiped.

Just buy second-hand HSMs off eBay, they often haven't been wiped, and the
PINs are conveniently taped to the case.  I have a collection of interesting
keys (or at least keys from interesting places, including government
departments) obtained in this way.

Peter.
___
The cryptography mailing list
cryptography@metzdowd.com
http://www.metzdowd.com/mailman/listinfo/cryptography

[Cryptography] Protecting Private Keys

2013-09-07 Thread Jeffrey I. Schiller
-BEGIN PGP SIGNED MESSAGE-
Hash: SHA1

While we worry about symmetric vs. public key ciphers, we should not
forget the risk of compromise of our long-term keys. How are they
protected?

One of the most obvious ways to compromise a cryptographic system is
to get the keys. This is a particular risk in TLS/SSL when PFS is not
used. Consider a large scale site (read: Google, Facebook, etc.) that
uses SSL. The private keys of the relevant certificates needs to be
literally on hundreds if not thousands of systems. Chances are they
are not encrypted on those systems so those systems can auto-restart
without human intervention. Those systems also break
periodically. What happens to the broken pieces, say a broken hard
drive?

If one of these private keys is compromised, all pre-recorded traffic
can now be decrypted, as long as PFS was not used (and as we know, it
is rarely used).

Encrypted email is also at great risk because we have no PFS in any of
these systems. Our private keys tend to last a long time (just look at
the age of my private key!).

If I was the NSA, I would be scavenging broken hardware from
“interesting” venues and purchasing computers for sale in interesting
locations. I would be particularly interested in stolen computers, as
they have likely not been wiped.

The bottom line here is that the NSA has upped the game (and probably
did so quite a while ago, but we are just learning about it now). This
means that commercial organizations that truly want to protect their
customers from the NSA, and other national actors whom I am sure are
just as skilled and probably more brazen, need to up their game, by a
lot!

- -Jeff

P.S. I am very careful about which devices my private key touches and
what happens to it when I am through with it.
-BEGIN PGP SIGNATURE-
Version: GnuPG v1.4.11 (GNU/Linux)

iD8DBQFSKzZE8CBzV/QUlSsRAqTsAJ4xJymTj04zCGF7v9OaZ4vJC3WoMgCfU1Qd
960tkxkWdrzz4ymCksyaKog=
=0JHf
-END PGP SIGNATURE-
___
The cryptography mailing list
cryptography@metzdowd.com
http://www.metzdowd.com/mailman/listinfo/cryptography

Re: [Cryptography] Protecting Private Keys

2013-09-07 Thread Phillip Hallam-Baker
On Sat, Sep 7, 2013 at 10:20 AM, Jeffrey I. Schiller j...@mit.edu wrote:


 If I was the NSA, I would be scavenging broken hardware from
 “interesting” venues and purchasing computers for sale in interesting
 locations. I would be particularly interested in stolen computers, as
 they have likely not been wiped.


+1

And this is why I have been so peeved at the chorus of attack against
trustworthy computing.

All I have ever really wanted from Trustworthy computing is to be sure that
my private keys can't be copied off a server.


And private keys should never be in more than one place unless they are
either an offline Certificate Signing Key for a PKI system or a decryption
key for stored data.

-- 
Website: http://hallambaker.com/
___
The cryptography mailing list
cryptography@metzdowd.com
http://www.metzdowd.com/mailman/listinfo/cryptography

Re: [Cryptography] Protecting Private Keys

2013-09-07 Thread Jim Popovitch
On Sat, Sep 7, 2013 at 10:20 AM, Jeffrey I. Schiller j...@mit.edu wrote:
 One of the most obvious ways to compromise a cryptographic system is
 to get the keys. This is a particular risk in TLS/SSL when PFS is not
 used. Consider a large scale site (read: Google, Facebook, etc.) that
 uses SSL. The private keys of the relevant certificates needs to be
 literally on hundreds if not thousands of systems.

$5k USD to anyone one of the thousands of admins with access

-Jim P.
___
The cryptography mailing list
cryptography@metzdowd.com
http://www.metzdowd.com/mailman/listinfo/cryptography