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https://cert.org

Infrastructure

· 9 checks — DNS, redirects, IPv6, crawlability, URL variants, and domain intelligence rolled into one auditable list.
SCORE
76
GRADE
C
FIX
2
REVIEW
3
PASS
4
INFO
0
Probed from Madrid, Spain
301 Moved Permanently
Checks
9
4 PASS 3 REVIEW 2 FIX
F
Redirect Chain
Action
3 redirect(s), 1388 ms total
FIX
3 redirect(s), 1388 ms total
Warning::
3 redirects before reaching final URL
Each redirect adds latency. Try to minimize the chain to 1 hop.
Info::
HTTP to HTTPS redirect present
Info::
WWW normalization redirect
Warning::
3-hop chain could be reduced to 1 hop
Redirect directly from https://cert.org to https://www.sei.cmu.edu/divisions/cert/
Warning::
Redirect overhead: 1388 ms total
Got: 1388 ms
Info::
Cross-domain redirect detected

https://cert.org

328 ms · HTTP/1.0

301

https://www.sei.cmu.edu/certsite/

375 ms · HTTP/1.1

301

http://www.sei.cmu.edu/divisions/cert/

208 ms · HTTP/1.0

301

https://www.sei.cmu.edu/divisions/cert/

477 ms · HTTP/1.1 FINAL

#URLStatusTimeProtocolServer
1https://cert.org301328 msHTTP/1.0BigIP
2https://www.sei.cmu.edu/certsite/301375 msHTTP/1.1
3http://www.sei.cmu.edu/divisions/cert/301208 msHTTP/1.0BigIP
4https://www.sei.cmu.edu/divisions/cert/200477 msHTTP/1.1

See the visual redirect chain in the HTTP Probe tab →

Each redirect adds latency. Try to minimize the chain to 1 hop.

Why this matters

Redirect chain — each hop adds latency; combine into one redirect where possible.

Source: Google Search Central / web.dev

Redirect directly from https://cert.org to https://www.sei.cmu.edu/divisions/cert/

Why this matters

Redirect chain could be flattened to one hop — server config tweak removes intermediate latency.

Source: web.dev

D
CDN & Delivery
Action
No CDN detected
FIX
No CDN detected
Warning::
No CDN detected
A CDN can significantly improve load times for users around the world by caching content at edge nodes closer to them.
No CDN detected

Consider using a CDN to improve global delivery speed and reduce origin load.

C
IPv6 Readiness
Action
No IPv6 support
REVIEW
No IPv6 support
Info::
No IPv6 (AAAA) records found
IPv6 support is increasingly important for global accessibility. About 40% of internet users have IPv6 connectivity.
No IPv6 Support
About 40% of internet users have IPv6. Consider adding AAAA records.

IPv6 support is increasingly important for global accessibility. About 40% of internet users have IPv6 connectivity.

Why this matters

No AAAA records — same impact as 'no IPv6 (AAAA) records'; IPv6-preferring clients pay extra latency falling back to IPv4.

Source: Google IPv6 stats

B
Crawlability
no robots.txt, no sitemap
REVIEW
no robots.txt, no sitemap
Info::
No robots.txt found
robots.txt is optional but recommended. It tells search engine crawlers which pages to index.
Info::
No sitemap.xml found
A sitemap helps search engines discover and index your pages more efficiently.

robots.txt is optional but recommended. It tells search engine crawlers which pages to index.

Why this matters

No robots.txt — crawlers fetch /robots.txt and get 404; not breaking but means default crawl behavior with no directives or sitemap reference.

Learn more

A minimal robots.txt with `User-agent: * / Allow: / / Sitemap: https://example.com/sitemap.xml` covers the basics. Without it, crawlers behave fine but lose the sitemap signal and can't be selectively blocked from crawl-traps.

Source: robotstxt.org

A sitemap helps search engines discover and index your pages more efficiently.

Why this matters

No sitemap.xml — Google relies on crawl-graph discovery alone, slowing indexing of deep or fresh URLs.

Learn more

A sitemap accelerates Google's discovery of new and updated content. Most CMSes auto-generate one; static-site frameworks need a build-step plugin. Reference it from robots.txt and submit in Search Console to confirm Google can fetch it.

Source: sitemaps.org / Google Search Central

robots.txt No robots.txt found

No robots.txt found

This is fine for most sites — a missing robots.txt allows all crawling by default.

sitemap.xml No sitemap found

No sitemap found

Adding a sitemap helps search engines discover your pages.

B
TLS Certificate Expiry & Recommendations
171 days until leaf cert expires — 3 issues to address
REVIEW

Certificate validity

171
days left
0d 30d 60d 90d+

Recommended actions

  • Enable HSTS: Strict-Transport-Security: max-age=31536000; includeSubDomains
  • Enable DNSSEC on your domain for DNS spoofing protection
  • Enable OCSP stapling on your TLS server to remove a CA roundtrip and protect user privacy
A+
DNS Records
1 A records, 52 ms lookup
PASS
1 A records, 52 ms lookup
Info::
Resolves to 1 IPv4 address(es)
Got: 147.72.252.242
Info::
Single A record — no DNS redundancy
Multiple A records provide failover if one server goes down.
Info::
No IPv6 (AAAA) records
Info::
4 nameserver(s) configured
Got: ns-916.awsdns-50.net, ns-1403.awsdns-47.org, ns-28.awsdns-03.com, ns-1794.awsdns-32.co.uk
Info::
2 mail exchanger(s) configured
Info::
CAA records not checked
CAA record lookup requires a specialized DNS resolver. This check will be available in a future update.
Info::
SPF record present in TXT
Info::
DNS resolution time: 52 ms
Got: 52 ms
A147.72.252.242
AAAA
CNAME
NSns-916.awsdns-50.net, ns-1403.awsdns-47.org, ns-28.awsdns-03.com, ns-1794.awsdns-32.co.uk
MX
10 tilton.sei.cmu.edu
10 tingley.sei.cmu.edu
TXT
MS=ms99326395
google-site-verification=XOhFzgbzrxnwXF_zY4WWTJSkIyRfIjEI8eaOJCx4WiI
GjlKiHz4O+yqufLrRIiCkmyaNeKDsFtlP0EdfJ5Hd0ERRCB3rBFfT0hjRz5KpuVbK7z1iW6Vh6MtnSK/...
SPF v=spf1 ip4:147.72.252.0/27 include:spf.protection.office365.us ?all
CAALookup not available with standard resolver
Resolved in 52 ms

Multiple A records provide failover if one server goes down.

Why this matters

Single A record means a single point of failure — if that IP goes down, your site is unreachable until DNS TTL expires.

Learn more

Add multiple A records for round-robin failover, or use a managed DNS provider with health-checked failover (Route 53, Cloudflare, NS1). Short TTL (60-300s) lets clients recover faster on outages.

Source: SRE practice / DNS architecture

CAA record lookup requires a specialized DNS resolver. This check will be available in a future update.

Why this matters

Informational: CAA (Certification Authority Authorization) records weren't checked in this scan.

A+
URL Variants
www/non-www, trailing slash, HTTP→HTTPS
PASS
www/non-www, trailing slash, HTTP→HTTPS
Info::
www/non-www redirect configured correctly (preferred: non-www)
Info::
HTTP correctly 301-redirects to HTTPS

www / non-www

301https://www.cert.org/
200https://cert.org/

Preferred variant: non-www

HTTP → HTTPS

301http://cert.org/ https://cert.org/

Consistent

A+
Domain Intelligence
cert.org — via Amazon Registrar, Inc., 34 years, 9 months old, hosted on CERT - Software Engineering Institute, US
PASS
cert.org — via Amazon Registrar, Inc., 34 years, 9 months old, hosted on CERT - Software Engineering Institute, US
Info::
Domain registered until Nov 18, 2034 (8 years, 8 months remaining)
Info::
DNSSEC is not enabled
DNSSEC protects against DNS spoofing attacks. While not required, enabling DNSSEC adds an additional layer of security. Contact your DNS provider to enable it.
Info::
Registrar: Amazon Registrar, Inc.
Warning::
Registrar lock is NOT enabled
The domain can be transferred without an unlock step. Enable registrar lock (clientTransferProhibited) in your registrar's control panel to protect against unauthorized or accidental transfers.
Info::
Hosting: CERT - Software Engineering Institute, US
Got: AS36407
Domain expiry

3080 days

November 18, 2034

SSL certificate

171 days

Issued by Internet2

Domain age

34 years, 9 months

Registered December 31, 1991

DNSSEC

Not enabled

Protects against DNS spoofing

Hosting

CERT - Software Engineering Institute, US

ASN AS36407

147.72.252.242

Registrar

Amazon Registrar, Inc.

Unlocked 4 NS records
Expiry timeline
Today
+1 year
Domain expiry SSL expiry Danger zone (≤30 days)
Recommended actions
  • Enable DNSSEC to protect visitors from DNS spoofing
  • Enable registrar lock (clientTransferProhibited) to block unauthorized domain transfers
Registrar Amazon Registrar, Inc.
Created December 31, 1991 (34 years, 9 months ago)
Expires November 18, 2034 (8 years, 8 months)
Last Updated March 2, 2026
Name Servers ns-1403.awsdns-47.org, ns-1794.awsdns-32.co.uk, ns-28.awsdns-03.com, ns-916.awsdns-50.net
DNSSEC Not enabled
Hosting
IP Address 147.72.252.242
ASN AS36407 (CERT - Software Engineering Institute, US)
Provider CERT - Software Engineering Institute, US
Data source: rdap (0.6s)

DNSSEC protects against DNS spoofing attacks. While not required, enabling DNSSEC adds an additional layer of security. Contact your DNS provider to enable it.

Why this matters

Without DNSSEC, an attacker who can poison your DNS can hijack your domain — and SSL certs alone don't stop them.

Learn more

DNSSEC adds cryptographic signatures to DNS records, preventing forged responses from poisoning resolver caches. Without it, an attacker who controls the network path can redirect your domain to a malicious server before any HTTPS handshake happens. Most modern registrars (Cloudflare, Google Domains, Route 53) enable it with one toggle.

Source: ICANN / RFC 4033

The domain can be transferred without an unlock step. Enable registrar lock (clientTransferProhibited) in your registrar's control panel to protect against unauthorized or accidental transfers.

Why this matters

Without registrar lock, an attacker who phishes your registrar credentials can transfer the domain in minutes — total brand hijack.

Learn more

Registrar lock (clientTransferProhibited, clientUpdateProhibited, clientDeleteProhibited) requires extra verification before any transfer/update/delete. Every major registrar offers it free. Combined with 2FA on your registrar account, it's the strongest defense against domain hijacking.

Source: ICANN / domain-security best practice

A+
HTTP Probe Timing
Total 360 ms — DNS, TCP, TLS, TTFB, content transfer breakdown
PASS
DNS Lookup DNS Lookup — time to resolve the domain name to an IP address.
45 ms
TCP Connect TCP Connect — time to establish a TCP connection to the server.
104 ms
TLS Handshake TLS Handshake — time to complete the HTTPS encryption handshake.
108 ms
Time to First Byte Time to First Byte — how long the server takes to respond with the first byte of data.
361 ms
Total Time Total request time from DNS lookup through full response.
361 ms

Connection waterfall

DNS Lookup 45 ms TCP Connect 104 ms TLS Handshake 108 ms Server Processing 104 ms Content Transfer 0 ms
All checks on this page are automated. Results are estimates - run targeted manual reviews when the score affects a release decision.

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