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Subject: Re: breach attack
From: Dirk-Willem van Gulik <dirkx@webweaving.org>
In-Reply-To: <20130810161404.GA29347@uio.no>
Date: Sat, 10 Aug 2013 18:19:15 +0200
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To: dev@httpd.apache.org


On 10 Aug 2013, at 18:14, "Steinar H. Gunderson" =
<sgunderson@bigfoot.com> wrote:

> On Sat, Aug 10, 2013 at 06:11:09PM +0200, Dirk-Willem van Gulik wrote:
>> I'd keep in mind that compression is simply an amplifier for this =
type of
>> attack. It makes the approach more effective. But it is not =
essential; when
>> you have in essence a largely known plaintext surrounding a short =
secret
>> and an oracle. And the latter is not going to go away - current =
dominant
>> site development models will make this worse; as do current =
operational
>> models w.r.t. to picking such up early.
>=20
> Wait, what's the oracle if there's no compression?


As as ultimately before - the origin server (and/or the traffic you =
compare it to). Granted - doing this raw is not that feasible for large =
key lengths - but even some slight weakness elsewhere (could be as silly =
as a render/timing change in the browser) will help.

Dw.=