Collaborate Disseminate
I would like to clarify the following scenario with DMARC, (assuming there is a publish DMARC policy):
SPF fails
No (aligned or any) DKIM records
Should result of DMARC check be none or fail? Technically we cannot align anything with F… Continue reading DMARC & failing SPF
I always thought that to authenticate email we needed both SPF and DKIM (and DMARC). But email is confusing and recently I found myself asking why we can’t do with just SPF or DKIM. I then discovered that the problem with using just SPF is… Continue reading Do we need SPF when we have DKIM?
If a mail sender encodes the sender address in the from: field, the Mail Transfer Agent only checks the sender after the unencoded @. In this way, protection mechanisms like SPF/DKIM/DMARC are subverted.
Is there are any mit… Continue reading how to mitigate mailsploit
I’ve seen this question asked before, but unfortunately, don’t understand the responses. I think its something to do with “from” headers being defined differently by different standards. I’ve added all the domains in the “from” to SPF rec… Continue reading Why is DMARC failing when SPF and DKIM are passing?
Recently we have encountered 2 instances of mass phishing attempts from 2 accounts using SendGrid although the SPF is published as hard fail for both without SendGrid records and only for the mail servers authorized to send. … Continue reading SendGrid emails ignoring SPF records for mass phishing attempts
After an incident, I have a question which answer’s I cannot find.
I cannot provide the real headers as they come from a client.
Let’s consider a company which uses an Office365 tenant as mail server. Its domain is example.c… Continue reading SPF and Office 365 email accounts spoofing other Office 365 email accounts
A friend received a spoofed email (from Bank of America using an uber.com address) which was correctly identified as ‘spam’ by Gmail. However, looking at the raw message it seems to have passed SPF, DKIM and DMARC checks.
1… Continue reading How did a phishing email pass SPF, DKIM and DMARC?
DMARC produces “pass” result if and only if at least one of SPF and DKIM checks pass. It has been noted that DKIM provides stronger protection of the two (if implemented properly). But, in order to require namely DKIM passing… Continue reading What is the reason for DMARC spec to not require specifically SPF or DKIM pass?
I have an app whose main purpose is to help people track emails they send.
In most user onboarding, The user is sent a secret URL via email. They validate by clicking a link to return the secret.
An alternative would be to… Continue reading Email verification by sending mail instead of receiving
I have spent a bit of time researching SPF, DKIM and DMARC mechanisms however If I understand correctly, these help the recipient to confirm whether the domain is legitimate but only if they have these mechanisms configured c… Continue reading SPF, DKIM and DMARC – How do receiving/recipient mail servers know how and when to validate the mail?