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On 03/22/2013 09:47 PM, From Jeremy Rowley:
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<p class="MsoNormal"><span style="color: rgb(31, 73, 125);">Why?
What risks do short lived certificates provide over other
types of certificates.</span></p>
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<br>
First of all I don't believe that there can be a robust mechanism to
issue certificates with such a frequency where the CA does its pre
and post issuance diligence. I'd consider such issuance more risky
than a controlled and supervised manner (assuming that CAs did
implement some due diligence for issuing certificates in the post
Diginotar aera). This is my main objection and critical in my
opinion.<br>
<br>
Second, for an attacker 3 - 7 days is a long time to achieve their
goals most of the time, by repeating same attack which would go
undetected due to the above mentioned missing diligence, this could
go on for a while.<br>
<br>
Third, most software (browsers and other clients) check revocation
usually on a higher frequency then possible nextUpdate fields in
OCSP and CRLs, specially when relying on OCSP. Removing revocation
status DPs will allow an attacker to complete his attack happily
even if the CA has become aware of it. Software updates wouldn't be
fast enough either.<br>
<br>
Forth, browsers don't check revocation status all at the same time,
making attacks more difficult when revocation status DPs are defined
(system restarts, first access, access after 24 hours depending on
software trigger a revocation status check). This will make an
attack less reliable and also detectable by the client (if
configured correctly).<br>
<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>
</tr>
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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>
</tr>
<tr>
<td>Blog: </td>
<td><a href="http://blog.startcom.org">Join the Revolution!</a></td>
</tr>
<tr>
<td>Twitter: </td>
<td><a href="http://twitter.com/eddy_nigg">Follow Me</a></td>
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