Hi Patrick,

>> can you please elaborate on where you see a security drawback
>> in the attack scenario you mentioned when using wildcard
>> certs over non-wildcard certs?
Principle of leat privilege dictates that only a single server (or
possibly related servers) be "authenticated". However, a wild card
will match all hosts(some hand waiving here)  - even if the host was
put in place by a bad guy. I'm aware of a couple of tools that will
flag it. Exchange's Security Analyzer is one of them.

A related attack from Black Hat:
http://www.blackhat.com/presentations/bh-dc-09/Marlinspike/BlackHat-DC-09-Marlinspike-Defeating-SSL.pdf.

If you're wondering why VeriSign, Comodo, and gang sell them, that's
easy - money.

Jeff

On Mon, Jun 7, 2010 at 5:37 AM, Eisenacher, Patrick
<[email protected]> wrote:
>> -----Original Message-----
>> From: Eisenacher, Patrick
>>
>> Hi Jeff,
>>
>> > -----Original Message-----
>> > From: Jeffrey Walton
>> >
>> > Hi Vieri,
>> >
>> > >> How does one issue a cert for multiple CN?
>> > >> Suppose I have just one HTTP server but it can be accessed
>> > >> via multiple FQDN... I suppose I need to use subjectAltName?
>> > >
>> > > Subject alternative name is one possibility. If you need
>> a cert for
>> > > several hosts/hostnames belonging to the same domain, a wildcard
>> > > CN comes to mind as well, eg. "*.domain.com".
>> > Wild carding usually makes the security folks cringe. A bad guy can
>> > stand up a malicious server, and the server appears legit to the
>> > outside world due to the wild card.
>>
>> can you please elaborate on where you see a security drawback
>> in the attack scenario you mentioned when using wildcard
>> certs over non-wildcard certs?
>
> Anybody else? Jeff's been MIA since a week and I still can't see why anybody 
> would cringe...
>
> Patrick Eisenacher
______________________________________________________________________
OpenSSL Project                                 http://www.openssl.org
User Support Mailing List                    [email protected]
Automated List Manager                           [email protected]

Reply via email to