DKIM-pass DMARC-fail via gappssmtp.com relay abuse on strict alignment policy
This rule monitors for incoming emails that pass DKIM authentication but fail DMARC verification, specifically where the signing domain is associated with Google Apps (gappssmtp.com). This pattern is often indicative of email spoofing, where an attacker sends mail from a legitimate provider's infrastructure but fails the domain alignment requirements of DMARC.
Splunk (SPL)
