Results for github.com
Analysis performed on April 15, 2026 at 02:49 PM
SPF
Warningv=spf1 ip4:192.30.252.0/22 include:spf.protection.outlook.com include:_netblocks.google.com include:_netblocks2.google.com include:mail.zendesk.com include:_spf.salesforce.com include:servers.mcsv.net include:mktomail.com include:sendgrid.net ip4:62.253.227.114 ip4:166.78.69.169 ip4:166.78.69.170 ip4:166.78.71.131 ~allDKIM
OKSelectors: google, selector1, k1, s1, s2, zendesk1, zendesk2, cmDMARC
Warningv=DMARC1; p=quarantine; sp=reject; pct=100; rua=mailto:dmarc@github.com; ruf=mailto:dmarc@github.com; fo=1MX
OKgithub-com.mail.protection.outlook.comRecommendations
1Upgrade your DMARC policy from p=quarantine to p=reject for full blocking
With p=quarantine, spoofed emails are sent to spam instead of being blocked outright. Some recipients still check spam folders, and sophisticated attacks can be flagged as legitimate by users. p=reject ensures fraudulent emails never reach any folder.
2Harden your SPF by replacing ~all with -all (hardfail)
With ~all (softfail), unauthorized senders are flagged but emails are usually still delivered. Switching to -all (hardfail) explicitly tells receiving servers to reject emails from unauthorized sources, providing much stronger protection against spoofing.
3Add MTA-STS to enforce TLS encryption for incoming emails
Without MTA-STS, an attacker performing a man-in-the-middle attack can downgrade the connection between mail servers to plaintext, intercepting emails in transit. MTA-STS tells sending servers to only deliver via TLS with a valid certificate, preventing downgrade attacks.
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