duckduckgo.com
HTTPS & TLS
91/100A- HTTP → HTTPS0/3
http://duckduckgo.com serves the site without encryption instead of redirecting to HTTPS.
Answer every plain-HTTP request with a 301 redirect to the same address on https://.
- HTTPS certificateDigiCert Inc10/10
HTTPS with a valid certificate from DigiCert Inc.
- Certificate expiry374/4
The certificate is valid for another 37 days.
- TLS versionTLS 1.34/4
Negotiates TLS 1.3, the current protocol: faster handshakes, forward secrecy always.
- Old protocols3/3
Refuses the retired TLS 1.0 and 1.1.
- Key strengthRSA 20482/2
A strong key: RSA 2048.
- HSTS1 year4/4
HSTS tells browsers to use HTTPS only, for 1 year.
- HTTP/2 and HTTP/3HTTP/22/2
HTTP/2.
DNS
79/100B- DNSSEC0/3
Not signed with DNSSEC: a forged DNS answer for the domain cannot be told from the real one.
- Name servers84/4
8 name servers for the domain.
- Name servers answer8/85/5
Every name server answers for the domain, with the same version of the zone.
- CAA recordsletsencrypt.org, digicert.com2/2
CAA records name the authorities allowed to issue its certificates.
- MTA-STS0/2
No MTA-STS: mail to the domain can be read in transit by stripping its encryption.
- SPF-all5/5
SPF lists the servers allowed to send its mail and rejects the rest (-all).
- DMARCreject7/7
DMARC tells receivers to reject mail that fakes the domain (p=reject).
- TLS reporting0.5/0.5
TLS reporting: senders report failed encrypted deliveries.
- DKIMselector12/2
A DKIM key is published (selector selector1), so its mail can be signed.
Web & network
75/100B- IPv60/4
duckduckgo.com has no IPv6 address: IPv6-only networks reach it only through translation.
- Content Security Policy3/3
A Content Security Policy limits which scripts the pages run.
- X-Content-Type-Options2/2
X-Content-Type-Options: nosniff stops browsers guessing file types.
- Framing2/2
Other sites cannot frame its pages (clickjacking protection).
- Referrer-Policyorigin0.5/0.5
Referrer-Policy limits what other sites learn about where visitors came from.
- Permissions-Policy0.5/0.5
Permissions-Policy turns off browser features the site does not use.
- RPKIvalid4/4
The route to the website is RPKI-valid: networks can reject hijacked announcements of it.
Dependencies
80/100B- One company for everythingMicrosoft Azure: website, email3/5
Microsoft Azure runs both the website and the email: one outage there takes both down.
- DNS providersNS1, quack-dns.com5/5
DNS is served by 2 providers: one can fail without taking the domain offline.
Who runs it
- Website
- Microsoft Azure
- DNS
- NS1quack-dns.com
- Microsoft 365
Routes
- 20.192.0.0/10AS8075RPKI valid
Name servers
- dns1.p05.nsone.netNS1AS62597
- dns2.p05.nsone.netNS1AS62597
- dns3.p05.nsone.netNS1AS62597
- dns4.p05.nsone.netNS1AS62597
- ns01.quack-dns.comquack-dns.comAS63911
- ns02.quack-dns.comquack-dns.comAS63911
- ns03.quack-dns.comquack-dns.comAS63911
- ns04.quack-dns.comquack-dns.comAS63911
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What is graded
A valid certificate (an invalid one means F), its expiry against its lifetime, TLS 1.3, no TLS 1.0/1.1 (else at most B), http:// sent straight to https://, HSTS, HTTP/2.
At least two name servers that all answer and agree, DNSSEC, CAA records, and a registration that is not about to expire.
SPF, a DMARC policy that rejects forgeries (none means at most B), MTA-STS and TLS reporting for domains that take mail, DKIM at common selectors.
Content Security Policy, nosniff, framing protection, Referrer- and Permissions-Policy, IPv6, and an RPKI-valid route (invalid means at most C).
DNS from more than one provider, and the website, DNS and email not all with one company.
A+ 95–100 · A 85–94 · B 75–84 · C 65–74 · D 50–64 · F below 50