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github.com

77/100

B

Scanned 2026-05-12

Cached result — add ?fresh=1 to force a new scan

Subcheck breakdown

Check	Status	Score
DMARC policy	reject	25/25
SPF record	warn	7/10
DKIM selector	found	10/10
TLS certificate	ok	20/20
WHOIS integrity	rate_limited	5/10
Subdomain takeover	ct_unavailable	10/15
MTA-STS / TLSRPT	missing	0/5
DNSSEC	unsigned	0/5

Recommendations

Simplify SPF includes on github.com — more than 10 DNS lookups causes SPF PermError
Publish MTA-STS: add _mta-sts.github.com TXT and host a policy at https://mta-sts.github.com/.well-known/mta-sts.txt
Enable DNSSEC on github.com — DS records must be published to the com zone by your registrar

Details

Area	Detail
DMARC	v=DMARC1; p=quarantine; sp=reject; pct=100; rua=mailto:dmarc@github.com; ruf=mailto:dmarc@github.com; fo=1
SPF	v=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
DKIM selectors	google, selector1, k2
TLS certificate	Ok (82 days remaining) — CN=Sectigo Public Server Authentication CA DV E36,O=Sectigo Limited,C=GB
WHOIS registrar	—
WHOIS expires	—
Subdomains	0 found
DNSSEC	Unsigned