Erik van Straten<p><span class="h-card" translate="no"><a href="https://toad.social/@grumpybozo" class="u-url mention" rel="nofollow noopener noreferrer" target="_blank">@<span>grumpybozo</span></a></span> : I don't fully agree with you.</p><p>I have no personal experience with Proofpoint, but I agree that Microsoft usually messes up security.</p><p>For example, it took Microsoft years to understand that bypassing ALL checks upto DMARC for senders in the user's list of "safe senders" (explicitly added, or implicitly because they were present in the user's personal address book) was one of their most stupid ideas ever (even if *that* list is long):</p><p><<< We also determined that the allowed sender and allowed domain lists in anti-spam policies and Safe Senders in Outlook were too broad and were causing more harm than good. >>><br><a href="https://learn.microsoft.com/en-us/defender-office-365/secure-by-default?view=o365-worldwide" rel="nofollow noopener noreferrer" translate="no" target="_blank"><span class="invisible">https://</span><span class="ellipsis">learn.microsoft.com/en-us/defe</span><span class="invisible">nder-office-365/secure-by-default?view=o365-worldwide</span></a></p><p>However, the problem here is not Microsoft or Proofpoint, but illusions created by marketeers of protocols such as SPF, DKIM, DMARC, ARC and BIMI.</p><p>Initially there are always nitwits (including Bill Gates) who predict that such protocols will kill spam. As expected (by people who understand), none of them did.</p><p>Then the nitwit marketeers will claim that, even if such a protocol does not stop spam, it'll kill phishing. As we know, none of those protocols did.</p><p>The reasons are simple:</p><p>1) Domain names are just (temporary) aliases to identities - like phone numbers. They may *seem* meaningful but are not.</p><p>Usually the identity-alias relation makes some sense, but only in one direction. Most people know that google.com belongs to Google. However, having seen aka.ms or goo.gl does make at least some people believe that the .ms TLD belongs to Microsoft and .gl to Google: they do not.</p><p>Typically (again) marketeers fail to understand this in general as well as the hierarchical nature of domain names. This lunacy leads to the fact that people are supposed to remember every domain name *precisely* that an organization may use (domain names have zero fault tolerance).</p><p>We learned that microsoft.com belongs to Microsoft, Inc. from Redmond.</p><p>However, why would (login.) microsoftonline.com also belong to that company? Which idiot "invents" such a name? Are their other servers offline or what? Why didn't they use login.microsoft.com?</p><p>And why does live.com belong to them? And passport.com, outlook.com? Okay, if that's the case, then why would microsofsignin.com, microsoft.login.com, lookout.com, microsoft.fail and microsoft.wtf *NOT* belong to Microsoft, Inc?</p><p>2) Most email programs hide the sender's SMTP-address anyway. As recipients typically do not get to see the originator's domain name, it may differ (unknowingly by the recipient) from the one suggested by the falsified text in the message. A different domain name may have their own SPF, DKIM and DMARC configuration set up correctly.</p><p>Unfortunately those protocols are not like "nothing's lost if they don't help"; they cause significant amounts of collateral damage.</p><p>SPF breaks email forwarding (there's an awkward "fix" for that problem - that someone else has to implement), and mailing list servers often break DKIM signatures. This has lead to the DMARC "fix" that if one of the SPF and DKIM checks fails, that's just fine. Which weakens the whole idea.</p><p>Every email admin has their own interpretation of optimal settings, such as what to do if an email originator specifies - (minus) or ~ in their SPF record. And they may "tune" them whenever they feel that it"s right.</p><p>The recipient usually does not know what the sending mail server asks the receiving mail server to do in case of SPF etc. errors or warnings, nor does the recipient usually know whether their receiving mail server honors such requests (and neither does the sender). Mail "should not be lost for frivolous reasons" but in practice it does.</p><p>Approximately half of the mails from the cryptography mailing list end up in my spam box, and my email address was unsubscribed from the full disclosure mailing list because of the excessive amount of bounces their server received from my internet provider's mail server.</p><p>Nested SPF DNS records may lead to unecpected failures because someone else changes a record leading to a list that becomes too long.</p><p>And this list goes on. It's a mess - while the problems that supposedly should have been solved, have not.</p><p>In the end: the easier impersonation is, the weaker authentication becomes. I.e. reliable authentication is HARD - in particular remote/online.</p><p><span class="h-card" translate="no"><a href="https://infosec.exchange/@fuzztech" class="u-url mention" rel="nofollow noopener noreferrer" target="_blank">@<span>fuzztech</span></a></span> <span class="h-card" translate="no"><a href="https://istoleyour.pw/@compuguy" class="u-url mention" rel="nofollow noopener noreferrer" target="_blank">@<span>compuguy</span></a></span> </p><p><a href="https://infosec.exchange/tags/Authentication" class="mention hashtag" rel="nofollow noopener noreferrer" target="_blank">#<span>Authentication</span></a> <a href="https://infosec.exchange/tags/Impersonation" class="mention hashtag" rel="nofollow noopener noreferrer" target="_blank">#<span>Impersonation</span></a> <a href="https://infosec.exchange/tags/SPF" class="mention hashtag" rel="nofollow noopener noreferrer" target="_blank">#<span>SPF</span></a> <a href="https://infosec.exchange/tags/DKIM" class="mention hashtag" rel="nofollow noopener noreferrer" target="_blank">#<span>DKIM</span></a> <a href="https://infosec.exchange/tags/DMARC" class="mention hashtag" rel="nofollow noopener noreferrer" target="_blank">#<span>DMARC</span></a> <a href="https://infosec.exchange/tags/ARC" class="mention hashtag" rel="nofollow noopener noreferrer" target="_blank">#<span>ARC</span></a> <a href="https://infosec.exchange/tags/DomainNames" class="mention hashtag" rel="nofollow noopener noreferrer" target="_blank">#<span>DomainNames</span></a> <a href="https://infosec.exchange/tags/Aliases" class="mention hashtag" rel="nofollow noopener noreferrer" target="_blank">#<span>Aliases</span></a></p>