Re: [TLS] WGLC for "Deprecating TLSv1.0 and TLSv1.1"

Peter Gutmann <> Fri, 10 May 2019 06:04 UTC

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From: Peter Gutmann <>
To: Hubert Kario <>, "" <>
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Thread-Topic: [TLS] WGLC for "Deprecating TLSv1.0 and TLSv1.1"
Date: Fri, 10 May 2019 06:04:23 +0000
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Subject: Re: [TLS] WGLC for "Deprecating TLSv1.0 and TLSv1.1"
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Martin Rex <> writes:

>What *WOULD* provide *HUGE* benefit, would be to remove the dangerous
>"protocol version downgrade dance" from careless applications, that is the
>actual problem known as POODLE, because this subverts the cryptographic
>procection of the TLS handshake protocol.

Is there anything apart from web browsers that engage in this silliness?  I've
never seen it, it's always just "connect with the one true protocol version
and suite" and that's it.

Now admittedly that might be TLS 1.0 with RSA key exchange being selected as
the one true protocol suite (in 2019!), but at least they don't do a downgrade

>And PLEASE stop unconditionally bashing SHA-1

+1.  It goes well beyond TLS, I've had some totally inane arguments with
people who just seem to want to repeat "SHA-1 bad! SHA-1 bad! SHA-1 bad!"
without being able to explain why it's bad when questioned, i.e. there's no
actual attack possible.  It's a problem when used with long-term signatures
like certs.  It's typically not a problem when used with anything else.