Blocking Spoofed Inbound Email - Office365
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Yes whoever is providing your dns to the outside world, youll neeed to make a txt record that has v=spf1 include:spf.protection.outlook.com -all
or something like that. -
@JaredBusch said in Blocking Spoofed Inbound Email - Office365:
@DustinB3403 said in Blocking Spoofed Inbound Email - Office365:
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.We have no SPF records setup on our domain at all...
It is technically a TXT record. Make sure you look in the right place.
It once was TXT, then it was it's own record and now it's back to being a TXT again.
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OK I found our records,
We have 4 in place at moment, the top one being what it should.
The other three are just weird.
@None 7200 correct spf address from what we can find.
@None 7200 google-site-verification=9832459823-45=- (some crap)
@None 3600 928640235(some crap)
@None 3600 21489789274563(some crap)We're checking with the MSP, see if they set these other 3 up for some reason, or if they know what they are.
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@DustinB3403 said in Blocking Spoofed Inbound Email - Office365:
OK I found our records,
We have 4 in place at moment, the top one being what it should.
The other three are just weird.
@None 7200 google-site-verification=9832459823-45=- (some crap)
@None 3600 928640235(some crap)
@None 3600 21489789274563(some crap)We're checking with the MSP, see if they set these other 3 up for some reason, or if they know what they are.
Those are not for SPF usage. Those are usually added for domain verificaiton purposes for services.
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@Dashrender said in Blocking Spoofed Inbound Email - Office365:
@JaredBusch said in Blocking Spoofed Inbound Email - Office365:
@DustinB3403 said in Blocking Spoofed Inbound Email - Office365:
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.We have no SPF records setup on our domain at all...
It is technically a TXT record. Make sure you look in the right place.
It once was TXT, then it was it's own record and now it's back to being a TXT again.
It was never anything but a TXT record officially. The native SPF record was proposed but never ratified into a standard.
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So you think the other 3 records are for something, but lord knows what?
And the one correct record that we have verified should be doing what it needs?
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@DustinB3403 said in Blocking Spoofed Inbound Email - Office365:
So you think the other 3 records are for something, but lord knows what?
And the one correct record that we have verified should be doing what it needs?
That first one is obviously for google to verify the site. Likely because your website setup google analytics.
Others are similar.
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Any reason not to post the real DNS record? It's completely public on the interwebs.
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@Dashrender because I don't actually have them when I said "I" I meant my boss was able to locate them, he paraphrased the records to me.
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I went way more basic...
I found out immediately that a sales site (hosted externally) uses a spoofed email address to work. That stopped working and I just put in an explicit rule for that outside source.
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https://technet.microsoft.com/en-us/library/dn789058(v=exchg.150).aspx
If one of those txt records doesnt say
v=spf1 include:spf.protection.outlook.com -all
It isnt correct for o365.
Yours may have some other include:external static ip address of mail server if you have local servers that send email out(spiceworks, backup appliance, etc) -
@BBigford said in Blocking Spoofed Inbound Email - Office365:
I went way more basic...
I found out immediately that a sales site (hosted externally) uses a spoofed email address to work. That stopped working and I just put in an explicit rule for that outside source.
That will stop internal users form seeing spoofed email, but that has nothing to do with the ability for spoofed email to be sent in your name though.
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You could also easily do an nslookup to confirm these records. Just make sure you set the type to txt, on Windows at least.
