Re: [Asrg] misconception in SPF
Martijn Grooten <martijn.grooten@virusbtn.com> Thu, 06 December 2012 20:47 UTC
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From: Martijn Grooten <martijn.grooten@virusbtn.com>
To: Anti-Spam Research Group - IRTF <asrg@irtf.org>
Thread-Topic: [Asrg] misconception in SPF
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Date: Thu, 06 Dec 2012 20:47:45 +0000
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Subject: Re: [Asrg] misconception in SPF
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So, to use a real-world example, what you're saying is that if you want to spoof Twitter, to avoid your email being caught by the -all in Twitter's SPF record, you could use foo.twitter.com as the sending domain and your email wouldn't be blocked because of an SPF fail. I think that's correct. You could also use aimport dot no (as some spammer sending a fake Twitter email did an hour ago). That domain doesn't have an SPF record either. As we're talking about the MAIL FROM in the SMTP envelope, which usually isn't shown to the user, I don't think this is a big problem. Perhaps your MTA or spam-filter does use the MAIL FROM in its decision whether to deliver the email or not. If it decides to deliver the message because it claims to come from Twitter, uses a subdomain of twitter.com and didn't fail SPF than that's very wrong. But I don't think it's SPF's fault. Martijn. ________________________________ Virus Bulletin Ltd, The Pentagon, Abingdon, OX14 3YP, England. Company Reg No: 2388295. VAT Reg No: GB 532 5598 33.
- Re: [Asrg] misconception in SPF John Levine
- [Asrg] misconception in SPF Christian Grunfeld
- Re: [Asrg] misconception in SPF Christian Grunfeld
- Re: [Asrg] misconception in SPF Derek Diget
- Re: [Asrg] misconception in SPF Martijn Grooten
- Re: [Asrg] misconception in SPF John Levine
- Re: [Asrg] misconception in SPF Christian Grunfeld
- Re: [Asrg] misconception in SPF Paul Smith
- Re: [Asrg] misconception in SPF Christian Grunfeld
- Re: [Asrg] misconception in SPF Andrew Sullivan
- Re: [Asrg] misconception in SPF Paul Smith
- Re: [Asrg] misconception in SPF darxus
- Re: [Asrg] misconception in SPF SM
- Re: [Asrg] misconception in SPF darxus
- Re: [Asrg] misconception in SPF Daniel Feenberg
- Re: [Asrg] misconception in SPF Paul Smith
- Re: [Asrg] misconception in SPF John Levine
- Re: [Asrg] various anti-spam techniques, was misc… John Levine
- Re: [Asrg] various anti-spam techniques, was misc… Rich Kulawiec
- Re: [Asrg] misconception in SPF SM
- Re: [Asrg] misconception in SPF Bill Cole
- Re: [Asrg] various anti-spam techniques, was misc… Christian Grunfeld
- Re: [Asrg] various anti-spam techniques, was misc… John Levine
- Re: [Asrg] misconception in SPF John Levine
- Re: [Asrg] misconception in SPF Alessandro Vesely
- Re: [Asrg] misconception in SPF Bill Cole
- Re: [Asrg] misconception in SPF Paul Smith
- Re: [Asrg] misconception in SPF Andrew Sullivan
- Re: [Asrg] misconception in SPF SM
- Re: [Asrg] misconception in SPF Dave Crocker
- Re: [Asrg] misconception in SPF Christian Grunfeld
- Re: [Asrg] misconception in SPF Dave Crocker
- Re: [Asrg] misconception in SPF Martijn Grooten
- Re: [Asrg] misconception in SPF John Levine
- Re: [Asrg] misconception in SPF Seth
- Re: [Asrg] misconception in SPF Christian Grunfeld
- Re: [Asrg] misconception in SPF John Levine
- Re: [Asrg] misconception in SPF John Levine
- Re: [Asrg] misconception in SPF Franck Martin
- Re: [Asrg] misconception in SPF Martijn Grooten
- Re: [Asrg] misconception in SPF Paul Smith
- Re: [Asrg] misconception in SPF Alessandro Vesely
- Re: [Asrg] misconception in SPF Martijn Grooten
- Re: [Asrg] misconception in SPF Dotzero
- Re: [Asrg] misconception in SPF Rich Kulawiec
- Re: [Asrg] misconception in SPF Christian Grunfeld
- Re: [Asrg] misconception in SPF Dave Crocker
- Re: [Asrg] misconception in SPF Chris Lewis
- [Asrg] whitelisting links (was Re: misconception … Dave Crocker
- Re: [Asrg] misconception in SPF Martijn Grooten
- Re: [Asrg] misconception in SPF Dave Crocker
- Re: [Asrg] misconception in SPF Christian Grunfeld
- Re: [Asrg] whitelisting links (was Re: misconcept… Paul Smith
- Re: [Asrg] misconception in SPF Martijn Grooten
- Re: [Asrg] whitelisting links (was Re: misconcept… Martijn Grooten
- Re: [Asrg] whitelisting links (was Re: misconcept… darxus
- Re: [Asrg] misconception in SPF Eggert, Lars
- Re: [Asrg] misconception in SPF Christian Grunfeld
- Re: [Asrg] whitelisting links (was Re: misconcept… Dave Crocker
- Re: [Asrg] whitelisting links (was Re: misconcept… Martijn Grooten
- Re: [Asrg] whitelisting links (was Re: misconcept… Michael Thomas
- Re: [Asrg] misconception in SPF John Levine
- Re: [Asrg] misconception in SPF Chris Lewis
- Re: [Asrg] whitelisting links (was Re: misconcept… Paul Smith
- Re: [Asrg] whitelisting links (was Re: misconcept… Steve Atkins
- Re: [Asrg] whitelisting links (was Re: misconcept… Martijn Grooten
- Re: [Asrg] whitelisting links (was Re: misconcept… Dave Crocker
- Re: [Asrg] whitelisting links (was Re: misconcept… Martijn Grooten
- Re: [Asrg] whitelisting links (was Re: misconcept… Christian Grunfeld
- Re: [Asrg] whitelisting links (was Re: misconcept… Dave Crocker
- Re: [Asrg] whitelisting links (was Re: misconcept… Chris Lewis
- Re: [Asrg] misconception in SPF Alessandro Vesely
- Re: [Asrg] whitelisting links (was Re: misconcept… Paul Smith
- Re: [Asrg] whitelisting links (was Re: misconcept… Martijn Grooten
- Re: [Asrg] misconception in SPF Martijn Grooten
- Re: [Asrg] whitelisting links (was Re: misconcept… Rich Kulawiec
- Re: [Asrg] whitelisting links (was Re: misconcept… Michael Thomas
- Re: [Asrg] misconception in SPF John Levine
- Re: [Asrg] whitelisting links (was Re: misconcept… John Johnson
- Re: [Asrg] misconception in SPF John Johnson
- Re: [Asrg] whitelisting links (was Re: misconcept… Michael Thomas
- Re: [Asrg] whitelisting links (was Re: misconcept… John Levine
- Re: [Asrg] misconception in SPF Dotzero
- Re: [Asrg] misconception in SPF John Levine
- Re: [Asrg] misconception in SPF Laura Atkins
- Re: [Asrg] DMARC, was misconception in SPF John Levine