Re: [dane] SMTP STARTTLS stripping in the wild
Viktor Dukhovni <ietf-dane@dukhovni.org> Fri, 14 November 2014 00:52 UTC
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Date: Fri, 14 Nov 2014 00:52:53 +0000
From: Viktor Dukhovni <ietf-dane@dukhovni.org>
To: dane@ietf.org
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References: <alpine.LFD.2.10.1411131457140.25815@bofh.nohats.ca> <20141114004313.8557.qmail@ary.lan>
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Subject: Re: [dane] SMTP STARTTLS stripping in the wild
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On Fri, Nov 14, 2014 at 12:43:13AM -0000, John Levine wrote: > >https://www.eff.org/deeplinks/2014/11/starttls-downgrade-attacks > > This is an anti-spam measure on port 25 traffic on a few mobile > networks. I expect there aren't a lot of copies of Postfix running > on mobile devices. For all those other mobile users, if they're > configured correctly they're submitting over port 587 or 465, and > nobody tries to filter that. Indeed most such configurations are likely to have similarly mundane explanations. I used Paul's message as an excuse for a marketing message, but forgot to voice my skepticism as to whether this is an actual attack at work. I am far more curious about what happened to Google's outbound TLS mail stats around Oct 14th: https://www.google.com/transparencyreport/saferemail/ but this seems likely to remain a mystery. Perhaps some large peer botched their TLS settings? -- Viktor.
- [dane] SMTP STARTTLS stripping in the wild Paul Wouters
- Re: [dane] SMTP STARTTLS stripping in the wild Viktor Dukhovni
- Re: [dane] SMTP STARTTLS stripping in the wild John Levine
- Re: [dane] SMTP STARTTLS stripping in the wild Paul Wouters
- Re: [dane] SMTP STARTTLS stripping in the wild John R Levine
- Re: [dane] SMTP STARTTLS stripping in the wild Chris Newman
- Re: [dane] SMTP STARTTLS stripping in the wild Viktor Dukhovni
- Re: [dane] SMTP STARTTLS stripping in the wild Michael Richardson
- Re: [dane] SMTP STARTTLS stripping in the wild Viktor Dukhovni