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On 07/27/2012 09:36 PM, From <a class="moz-txt-link-abbreviated" href="mailto:kirk_hall@trendmicro.com:">kirk_hall@trendmicro.com:</a>
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<p class="MsoNormal">Jeremy, even if an attacker could cache and
supply a previously good response (clearly a problem) –
wouldn’t that be the rare case?
<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">More likely a short lived cert might be
revoked soon after issuance because of a key compromise, etc.
– in those cases, quick revocation with required OCSP
responses would, in fact, deliver correct revocation
information (“revoked”) to the vast majority of relying
parties (as no attacker would be devilishly supplying cached
but incorrect good responses to relying parties in those
cases).<o:p></o:p></p>
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<br>
We have been through this discussion already a few times and one of
the clear risks involved that nobody seems to consider right now is
the necessity to issue new certificates on a regular basis
(turn-over) very frequently and most likely in an automated fashion.
Those certificates will also have to be installed in a similar
(automated) manner. There are risks when doing so and removes the
ability to closely monitor issuance and review of the certificates
or at least it makes it a lot harder, being it at the CA or at the
subscriber side. Assuming that every week a bunch of those
certificates have be pushed out, with increasing numbers the risk
grows exceptionally.<br>
<br>
A CA that issues tens or hundred of thousands of certificates per
year would have to issue the same amount of certificates times 52. I
can't see how any due diligence can be done here. And done tell me
that the issuing systems are all secured beyond any doubt that no
human intervention and monitoring is necessary.<br>
<br>
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<td colspan="2">Regards </td>
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<td colspan="2"> </td>
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<td>Signer: </td>
<td>Eddy Nigg, COO/CTO</td>
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<td> </td>
<td><a href="http://www.startcom.org">StartCom Ltd.</a></td>
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<td>XMPP: </td>
<td><a href="xmpp:startcom@startcom.org">startcom@startcom.org</a></td>
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<td>Blog: </td>
<td><a href="http://blog.startcom.org">Join the Revolution!</a></td>
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<td>Twitter: </td>
<td><a href="http://twitter.com/eddy_nigg">Follow Me</a></td>
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