Re: [TLS] TLS 1.3 - Support for compression to be removed

Dave Garrett <> Sun, 04 October 2015 18:55 UTC

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From: Dave Garrett <>
Date: Sun, 04 Oct 2015 14:55:23 -0400
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Subject: Re: [TLS] TLS 1.3 - Support for compression to be removed
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On Sunday, October 04, 2015 02:48:19 pm Jeffrey Walton wrote:
> If I am reading things correctly: the group has effectively
> encountered a security problem, deemed it to be too hard for them, and
> then pushed it into another layer where folks are even less equipped
> to deal with it. Is that correct?
> I might be missing something, but I don't believe the "problems
> created by compression" have gone away. Rather, they have been moved
> around so the risk remains. The underlying problem still exists
> because the group responsible for providing those security services
> have not addressed them.

TLS & SPDY + HTTP compression was broken due to CRIME. The fix was to disable it, and then HTTP/2 introduced HPACK to compress headers safely. Yes, the security issue has been moved around, but to a place that can actually fix it properly. There is nothing TLS could do to implement a fix like HPACK here. I don't claim this is the only way to fix this problem, but it is a straightforward one and the one that is being done.