Re: [TLS] Another IRINA bug in TLS

Peter Gutmann <pgut001@cs.auckland.ac.nz> Thu, 21 May 2015 06:10 UTC

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From: Peter Gutmann <pgut001@cs.auckland.ac.nz>
To: Nikos Mavrogiannopoulos <nmav@redhat.com>, Watson Ladd <watsonbladd@gmail.com>
Thread-Topic: [TLS] Another IRINA bug in TLS
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Date: Thu, 21 May 2015 06:10:08 +0000
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Subject: Re: [TLS] Another IRINA bug in TLS
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Nikos Mavrogiannopoulos <nmav@redhat.com>; writes:
>On Wed, 2015-05-20 at 10:05 -0400, Watson Ladd wrote:
>> https://weakdh.org/
>>
>> Transcript hashing will solve this problem. In the meantime, you want
>> to turn off DH_EXPORT.
>
>The interesting thing is that there are no DHE_EXPORT ciphersuites.

No, the interesting thing (or more accurately the MASSIVE SCREAMING WTF) is
that there are widely-deployed web server and browser implementations out
there that will still use 512-bit keys.  Not custom embedded environments
where you're using TLS as a privacy screen and anything that counters basic
packet sniffing is just fine, but production public-internet web servers and
browsers.  The point to make isn't "fancy security mechanism X would have
prevented this" but "why are these things still using crypto at the level of
RC4_40_WITH_MD5" in 2015?

Peter.