North American Network Operators Group Date Prev | Date Next | Date Index | Thread Index | Author Index | Historical Re: Buying and selling root certificates
Self signed certificate protects you against any _short term_ attack - insuregent must maintain his own certificate, interceipt your connections, redirect my packets _BEFORE_ I connect very first time (after it, I got certificate and am protected). So, it is reasonable (to use commercial certificates) for public financial services (banks, e-commerce); all other kinds of services do not require it - all insurgent can do is to fraud you once in a life... unrealistic scenario. Certificate Authorities are a very good example of _blown up_ business. (Yes, they verify identity... what the difference, if you maintain 1 or 100 domains under the same company name and same basic level domains... Certificate should cost 20% for 1 year, not 400$). Do not overestimate importance of it... it is more for the public relations, not for the real security. (but I never propose any bank, any point of sale, any e-commerce to use self-signed certificate for _public_ service... even if risk is 0.000001%).. ----- Original Message ----- From: "Steven M. Bellovin" <[email protected]> To: "Sean Donelan" <[email protected]> Cc: <[email protected]> Sent: Wednesday, April 28, 2004 6:05 PM Subject: Re: Buying and selling root certificates > > In message <[email protected]>, Sean Donelan > writes: > > > >Not that SSL certificates are worth the paper they aren't printed > >on; I still find this vaguely disturbing. Just who do you think your > >computer is trusting? > > > >http://www.websheji.com/domain-names/news/id506.html > > Bob Parsons, CEO of Go Daddy, said that Starfield Technologies, a > > subsidiary of the company, bought an unused root certificate, trusted by > > 99% percent of the browsers from ValiCert Inc more than a year ago has > > been developing the system since then. > > > >I'm not that interested in SSL for web servers, but I have noticed a > >gradual increase in the number of mail servers willing to STARTTLS with > >mine. I was experimenting with trying to verify some of the certificates > >presented, its not real security, but makes the logs cleaner. > > Matt Blaze said it well: "A commercial CA will protect you from anyone > from whom they won't take money." > > Put another way, what's your threat model? Against what threats are > you trying to defend yourself? Rob Seastrom seems to be trying to > defend himself against passive eavesdroppers, for which SSL without > certificate verification is an entirely adequate defense. If your > concern is phishing, however, you need to check the certificate chain, > the policies of the trust anchor (AKA "root CA"), and its reputation > for actually enforcing those policies with proper verification. > Verisign, for example, was fooled a few years ago by someone who > claimed to be Microsoft -- but they had sufficient back-end > verification that the spoof was detected. Is this good enough? What's > your threat model...? > > > --Steve Bellovin, http://www.research.att.com/~smb > >
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