Re: [TLS] Deprecating TLS 1.0, 1.1 and SHA1 signature algorithms

Peter Gutmann <pgut001@cs.auckland.ac.nz> Tue, 12 January 2016 02:02 UTC

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From: Peter Gutmann <pgut001@cs.auckland.ac.nz>
To: Watson Ladd <watsonbladd@gmail.com>
Thread-Topic: [TLS] Deprecating TLS 1.0, 1.1 and SHA1 signature algorithms
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Date: Tue, 12 Jan 2016 02:01:55 +0000
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Subject: Re: [TLS] Deprecating TLS 1.0, 1.1 and SHA1 signature algorithms
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Watson Ladd <watsonbladd@gmail.com>; writes:

>Do the RFCs require the relevant checks or not?

No, they just specify the algorithms and bits on the wire (with a side-order
of MTI stuff for interoperability).  It's up to implementers to not do stupid
things.

>That's because real cryptographers understand that this is only 64 times
>better then SHA1, and so don't bother to mention it.

If it's so trivial to compromise then why, of all the many, many papers
attacking TLS, has no-one every published an attack based on this?  In fact,
since it's so easy, perhaps you could publish a paper demonstrating it in
practice?

Peter.