Re: [TLS] Another IRINA bug in TLS

Karthikeyan Bhargavan <karthik.bhargavan@gmail.com> Mon, 25 May 2015 12:26 UTC

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From: Karthikeyan Bhargavan <karthik.bhargavan@gmail.com>
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Date: Mon, 25 May 2015 14:26:52 +0200
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To: Hubert Kario <hkario@redhat.com>
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Subject: Re: [TLS] Another IRINA bug in TLS
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On 25 May 2015, at 14:02, Hubert Kario <hkario@redhat.com> wrote:

>> Hubert Kario's latest results on
>> https://securitypitfalls.wordpress.com/2015/03/29/march-2015-scan-results/
>> show:
>> EXP-EDH-RSA-DES-CBC-SHA 22110     4.5043%
> 
> hmm, that is a bit big difference...
> 
> If I ignore the "trust" bit in results I'm still getting just:
> EXP-EDH-RSA-DES-CBC-SHA 41804     6.2565

At weakdh.org, we use numbers from the ZMap scans (https://scans.io/)

In March 2015, the number of servers supporting for TLS_DHE_*_EXPORT_* were:

Alexa Top 1M:      45 K hosts out of 539K HTTPS hosts (4.9%)
Browser-trusted : 706K hosts out of 14.3M HTTPS hosts with browser trusted certs (8.4%)

We think the numbers should have gone down some, partly due to servers turning off *_EXPORT_*
in the wake of FREAK (but sadly, not nearly enough servers reacted to FREAK).

Best,
Karthik






> 
> From 668168 sample.
> 
> But then there is something which matches rather well the percentage:
> EDH-RSA-DES-CBC-SHA     75939     11.3653
> (note the lack of "EXP-")
> -- 
> Regards,
> Hubert Kario
> Quality Engineer, QE BaseOS Security team
> Web: www.cz.redhat.com
> Red Hat Czech s.r.o., Purkyňova 99/71, 612 45, Brno, Czech Republic_______________________________________________
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