Subject: RE: caCompromise

From: Ambarish Malpani <[email-masked]>
Date: Wed, 27 Jun 2001 07:45:49 -0700

Hi Paul,
    The other place where the reason code of caCompromise becomes
important is when a root is compromised. I don't think most
applications check the status of a root certificate. In that
case, it is important to revoke *all* certificates with the
reason of caCompromise. Ofcourse, this works better with OCSP
than with CRLs, because with CRLs, you can only revoke certificates
that you "know" you have issued. With OCSP, you can revoke any
certificate that somebody tries to check. [Caveat: The person
who compromises the root could always issue new certificates with
AIAs that point to some other responder]

Regards,
Ambarish

---------------------------------------------------------------------
Ambarish Malpani
Architect                                                650.567.5457
ValiCert, Inc.                                  [email-masked]
339 N. Bernardo Ave.                          http://www.valicert.com
Mountain View, CA 94043

> -----Original Message-----
> From: Paul Gogarty [mailto:[email-masked]]
> Sent: Wednesday, June 27, 2001 4:01 AM
> To: [email-masked]; [email-masked]; 
> [email-masked];
> [email-masked]
> Subject: caCompromise
> 
> 
> 
> Revoking the CA certificate will deny the use of an end 
> entity certificate
> (if the validity of the certification path is properly 
> checked). But the end
> entity certificate is not revoked.
> 
> I was under the impression that caCompromise provided a 
> revocation reason so
> that end entity certificates could be revoked for completeness if a CA
> became compromised.
> 
> Whether or not end entity certificates should be revoked due to a CA
> compromise leads into the same grey area as whether or not to revoke
> certificates in the case of accidental destruction of an end 
> entity key
> pair. But in this case there is a revocation reason provided 
> to deal with
> the revocation of end entity certificates, allowing CAs to 
> define there own
> policy of what to do in the event of a CA compromise.
> 
> -----Original Message-----
> From: [email-masked] [mailto:[email-masked]]
> Sent: Thursday, June 21, 2001 2:45 AM
> To: [email-masked]; [email-masked]; [email-masked];
> [email-masked]
> Subject: RE: Revoking bogus certificates
> 
> 
> "Paul Gogarty" <[email-masked]> writes:
> 
> >>(Looking through the codes again, what *is* a caCompromise, 
> as opposed to
> a
> >>keyCompromise?  Could this be used for neverValid 
> (caCompromise implies
> they
> >>issued the cert in error)?  OTOH a CMP-style "undo" isn't really a
> >>caCompromise, and it's possible that many CAs won't like 
> using a reason
> code
> >>which implies they screwed up).
> >
> >It was my understanding that caCompromise signalled that the 
> certificate
> had
> >been revoked because the private key of the CA had become 
> compromised.
> 
> Wouldn't that be handled by revoking the CA's key with a 
> reason code of
> keyCompromise?
> 
> Peter.
> 
>