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Re: [TLS] The TLS_FALLBACK_SCSV time bomb (was: Re: Working Group Last Call for draft-ietf-tls-downgrade-scsv-00)

Marsh Ray <maray@microsoft.com> Fri, 17 October 2014 23:49 UTC

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From: Marsh Ray <maray@microsoft.com>
To: Andrei Popov <Andrei.Popov@microsoft.com>, Martin Thomson <martin.thomson@gmail.com>
Thread-Topic: [TLS] The TLS_FALLBACK_SCSV time bomb (was: Re: Working Group Last Call for draft-ietf-tls-downgrade-scsv-00)
Thread-Index: AQHP6g/w1BhRgIoKW0S6M5mRt7fur5w0TqsAgABoBICAAAjbgIAAB9GAgAAJh4CAACPrIA==
Date: Fri, 17 Oct 2014 23:49:05 +0000
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References: <2112FCAD-4820-49D9-9871-6501C83A554D@cisco.com> <543F9893.806@redhat.com> <543FA0A0.1030205@polarssl.org> <543FCAED.50502@redhat.com> <2A0EFB9C05D0164E98F19BB0AF3708C71D39ECECB4@USMBX1.msg.corp.akamai.com> <5440E005.6000607@redhat.com> <180027849.13041583.1413544466157.JavaMail.zimbra@redhat.com> <CADMpkcL2mntDd0dOruziqF0F=xURnqGgd_YkpF+ONzz8v-wQ9Q@mail.gmail.com> <1354095824.13104897.1413553221955.JavaMail.zimbra@redhat.com> <CADMpkcLRCsfQSr0=f97kXJw3RwHN5A79MYQ2j7XaxPxUy2MCLg@mail.gmail.com> <CABkgnnUBYtWUY-CZDDzFiDpMWYbca74o6kejh2Q3L+FHVaHoOA@mail.gmail.com> <d8ce6c7437404bcbbea3a17e5c0b1582@BL2PR03MB419.namprd03.prod.outlook.com> <CABkgnnVJZhr3sD5iobbyLu-Vw3_i477zcbLFr-P+YB7RiKUtfg@mail.gmail.com> <7fe248e5b4374fbd8d04ff460bc3ace8@BL2PR03MB419.namprd03.prod.outlook.com>
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Cc: "tls@ietf.org" <tls@ietf.org>
Subject: Re: [TLS] The TLS_FALLBACK_SCSV time bomb (was: Re: Working Group Last Call for draft-ietf-tls-downgrade-scsv-00)
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From: TLS [mailto:tls-bounces@ietf.org] On Behalf Of Andrei Popov
> It's not an RFC yet, so perhaps we should at least consider using
> a TLS extension. SCSVs are ugly hacks. A simple TLS
> extension is probably not much harder to implement than
> an SCSV, and may result in cleaner code.

At least I think I remember hearing somewhere that
"SSLv3 without extensions" is one of the configurations that some
of these auto-downgrading client applications fall back to.

- Marsh

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