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Security

· 13 checks — HTTP headers, CSP, TLS handshake, and cookie hygiene rolled into one auditable list.
SCORE
57
GRADE
D
FIX
5
REVIEW
3
PASS
5
INFO
0
Checks
13
5 PASS 3 REVIEW 5 FIX
F
Security Headers
Action
2 of 10 headers properly configured
FIX
2 of 10 headers properly configured
Critical::
HSTS header is missing
Strict-Transport-Security forces browsers to use HTTPS, preventing downgrade attacks. Add the header with a max-age of at least 1 year.
Expected: max-age=31536000; includeSubDomains
Warning::
X-Content-Type-Options header is missing
This header prevents MIME-type sniffing, which can lead to XSS attacks. Set it to 'nosniff'.
Expected: nosniff
Warning::
X-Frame-Options header is missing
This header prevents clickjacking by controlling who can embed your page in a frame. Set it to DENY or SAMEORIGIN.
Expected: DENY
Warning::
Referrer-Policy header is missing
Controls how much referrer information is sent with requests. Set to 'strict-origin-when-cross-origin' or stricter.
Expected: strict-origin-when-cross-origin
Warning::
Permissions-Policy header is missing
Controls which browser features (camera, microphone, geolocation) are allowed. Set it to restrict unused features.
Expected: geolocation=(), camera=(), microphone=()
Critical::
Content-Security-Policy header is missing
CSP is the most important header for preventing XSS attacks. See the CSP section for detailed analysis.
Expected: default-src 'self'
Warning::
Cross-Origin-Opener-Policy header is missing
COOP isolates your browsing context, preventing cross-origin side-channel attacks. Set to 'same-origin'.
Expected: same-origin
Warning::
Cross-Origin-Embedder-Policy header is missing
COEP prevents loading cross-origin resources without explicit permission. Required for SharedArrayBuffer and high-resolution timers.
Expected: require-corp
Info::
X-Powered-By header is not present
Info::
Server header is present without version info
Got: LiteSpeed
Info::
Domain is not in the Chrome HSTS preload list (status: unknown)
Submit your domain to hstspreload.org to close the trust-on-first-use gap. Requires a preload-ready HSTS header (max-age=31536000+, includeSubDomains, preload).
Got: unknown

Strict-Transport-Security forces browsers to use HTTPS, preventing downgrade attacks. Add the header with a max-age of at least 1 year.

Expected: max-age=31536000; includeSubDomains
Why this matters

Without HSTS, a network attacker can downgrade the very first connection to HTTP and steal the user's session.

Learn more ▾

HSTS tells browsers 'never speak HTTP to this domain again.' Without it, a network attacker (public WiFi, malicious ISP, hostile DNS) intercepts the first HTTP attempt and serves a downgraded version of your site. One header, big surface reduction.

Source: RFC 6797 / OWASP

CSP is the most important header for preventing XSS attacks. See the CSP section for detailed analysis.

Expected: default-src 'self'
Why this matters

Without a CSP, a single XSS bug can exfiltrate everything your users type — including credentials.

Learn more ▾

Content-Security-Policy is the browser-enforced firewall against XSS. With a strict CSP, a script injection that would otherwise steal session cookies or rewrite the page is silently blocked. Without it, your only defense is hoping every input on every form is escaped correctly forever.

Source: OWASP / MDN

This header prevents MIME-type sniffing, which can lead to XSS attacks. Set it to 'nosniff'.

Expected: nosniff
Why this matters

MIME sniffing lets browsers run uploaded files as JavaScript, turning a file upload into an XSS.

Learn more ▾

Setting X-Content-Type-Options: nosniff tells browsers to trust your declared Content-Type instead of guessing. Without it, an attacker who uploads a polyglot file can sometimes get it executed as a script. One header, no downside.

Source: OWASP / MDN

This header prevents clickjacking by controlling who can embed your page in a frame. Set it to DENY or SAMEORIGIN.

Expected: DENY
Why this matters

Without frame protection, your site can be embedded in a hostile page and used for clickjacking.

Learn more ▾

Clickjacking overlays your site under a transparent malicious page so users click invisible buttons. Setting X-Frame-Options: DENY (or a modern frame-ancestors CSP directive) blocks the embedding entirely. There's almost never a legitimate reason to allow it.

Source: OWASP / MDN

Controls how much referrer information is sent with requests. Set to 'strict-origin-when-cross-origin' or stricter.

Expected: strict-origin-when-cross-origin
Why this matters

Default browser behavior leaks full URLs (including query params and tokens) to every third-party resource — set a strict policy.

Learn more ▾

Without a Referrer-Policy header, browsers send the full referring URL with images, scripts, and fonts loaded from third-party origins. URLs containing tokens, user IDs, or session params end up in third-party logs. Set `Referrer-Policy: strict-origin-when-cross-origin` (or stricter) to limit leakage.

Source: MDN / W3C

Controls which browser features (camera, microphone, geolocation) are allowed. Set it to restrict unused features.

Expected: geolocation=(), camera=(), microphone=()
Why this matters

Permissions-Policy locks down browser APIs you don't use — without it, every page can request camera/mic/geolocation if XSS lands.

Learn more ▾

By default every page can request the camera, microphone, geolocation, payment APIs, and dozens more. Permissions-Policy turns off the ones you don't need so a future bug can't quietly start using them. It's a defense-in-depth header — one line, big surface reduction.

Source: MDN / W3C

COOP isolates your browsing context, preventing cross-origin side-channel attacks. Set to 'same-origin'.

Expected: same-origin
Why this matters

COOP isolates your top-level browsing context from cross-origin windows — without it, popup-based side-channel attacks remain possible.

Learn more ▾

Cross-Origin-Opener-Policy: same-origin prevents cross-origin pages from sharing a browsing-context group with yours. This blocks cross-window references that enable Spectre-style timing attacks and tab-nabbing. Required if you want to enable SharedArrayBuffer.

Source: MDN / web.dev

COEP prevents loading cross-origin resources without explicit permission. Required for SharedArrayBuffer and high-resolution timers.

Expected: require-corp
Why this matters

COEP enforces that all embedded resources opt-in to cross-origin embedding — required for cross-origin isolation features.

Learn more ▾

Cross-Origin-Embedder-Policy: require-corp ensures every embedded resource (script, iframe, image) explicitly allows being loaded cross-origin. Combined with COOP, this enables the cross-origin-isolated context that unlocks SharedArrayBuffer, high-resolution timers, and other powerful APIs.

Source: MDN / web.dev

Submit your domain to hstspreload.org to close the trust-on-first-use gap. Requires a preload-ready HSTS header (max-age=31536000+, includeSubDomains, preload).

Why this matters

Not in the Chrome preload list — first-time visitors over plain HTTP can be downgraded by a network attacker before HSTS kicks in.

Learn more ▾

The HSTS header only protects users who have already visited the site (TOFU window). Adding your domain to the Chrome preload list closes that gap so HSTS is enforced from the very first connection. Requires a preload-ready header (max-age=31536000+, includeSubDomains, preload) then submission at hstspreload.org. Inclusion ships in the next Chrome release after acceptance.

Source: hstspreload.org

F
Content Security Policy
Action
No enforcing CSP policy found
FIX
No enforcing CSP policy found
Critical::
No Content-Security-Policy header found
CSP is the most effective defense against XSS attacks. Add a Content-Security-Policy header to restrict resource loading.
Expected: default-src 'self'

CSP is the most effective defense against XSS attacks. Add a Content-Security-Policy header to restrict resource loading.

Expected: default-src 'self'
Why this matters

Without a CSP, a single XSS bug can exfiltrate everything users type — credentials, payment data, session tokens.

Learn more ▾

Content-Security-Policy is the browser-enforced firewall against XSS. With a strict CSP, a script injection that would otherwise steal session cookies is silently blocked. Without it, your only defense is hoping every input on every form is escaped correctly forever. Start in Report-Only mode, fix violations, then graduate to enforcing.

Source: OWASP / MDN

F
Subresource Integrity
Action
0 of 5 external resources have SRI
FIX
0 of 5 external resources have SRI
Warning::
External link from cdnjs.cloudflare.com lacks integrity attribute
Without SRI, if this CDN is compromised, attackers could inject malicious code.
Got: https://cdnjs.cloudflare.com/ajax/libs/uikit/3.0.3/css/uikit.min.css
Warning::
External script from www.googletagmanager.com lacks integrity attribute
Without SRI, if this CDN is compromised, attackers could inject malicious code.
Got: https://www.googletagmanager.com/gtm.js?id=GTM-T8Z9663
Warning::
External script from cdnjs.cloudflare.com lacks integrity attribute
Without SRI, if this CDN is compromised, attackers could inject malicious code.
Got: https://cdnjs.cloudflare.com/ajax/libs/uikit/3.0.3/js/uikit.min.js
Warning::
External script from cdnjs.cloudflare.com lacks integrity attribute
Without SRI, if this CDN is compromised, attackers could inject malicious code.
Got: https://cdnjs.cloudflare.com/ajax/libs/uikit/3.0.3/js/uikit-icons.min.js
Warning::
External link from fonts.googleapis.com lacks integrity attribute
Without SRI, if this CDN is compromised, attackers could inject malicious code.
Got: https://fonts.googleapis.com/css?family=Quicksand:400
SRI Coverage 0 / 5 of external resources have integrity hashes
TagDomainIntegrity
<link>cdnjs.cloudflare.com✗ Missing
<script>www.googletagmanager.com✗ Missing
<script>cdnjs.cloudflare.com✗ Missing
<script>cdnjs.cloudflare.com✗ Missing
<link>fonts.googleapis.com✗ Missing
F
Email Security
Action
no DMARC
FIX
no DMARC
Warning::
No DMARC record found
Without DMARC, email receivers have no policy for handling authentication failures. Add a TXT record at _dmarc.<domain> starting with v=DMARC1.
Info::
No DKIM detected via common selectors
DKIM signs outbound mail to prove origin. We probed common selectors (default, google, selector1, etc.) without finding a record. If you use a non-standard selector, this is a false negative.
Info::
MTA-STS not configured
MTA-STS forces inbound mail to use TLS, preventing downgrade attacks. Requires both a TXT record at _mta-sts.<domain> and a policy file at https://mta-sts.<domain>/.well-known/mta-sts.txt.
Info::
TLS-RPT not configured
TLS-RPT (RFC 8460) lets MTAs report TLS-handshake failures, so you can detect and fix MTA-STS misconfigurations. Add a TXT record at _smtp._tls.<domain>.
DMARC

No DMARC record found

Without DMARC, email receivers have no policy for handling authentication failures from your domain.

Without DMARC, email receivers have no policy for handling authentication failures. Add a TXT record at _dmarc.<domain> starting with v=DMARC1.

Why this matters

Without DMARC, anyone can send phishing emails using your domain name.

Learn more ▾

DMARC tells receiving mail servers what to do with email that fails SPF/DKIM checks for your domain. With a strict 'p=reject' policy, spoofed emails get bounced; without it they reach the inbox. Domains used in phishing campaigns lose deliverability and brand trust fast.

Source: DMARC.org / NIST

DKIM signs outbound mail to prove origin. We probed common selectors (default, google, selector1, etc.) without finding a record. If you use a non-standard selector, this is a false negative.

Why this matters

No DKIM signature on outbound mail — receivers can't cryptographically prove the message came from your domain.

Learn more ▾

DKIM signs outbound mail with a private key whose public half lives in DNS at <selector>._domainkey.<domain>. Without DKIM, DMARC alone can't tell legitimate mail from spoofs, and large mailbox providers (Gmail, Yahoo) increasingly require DKIM for inbox placement. Note: this check probes a curated list of common selectors; non-standard selectors produce a false negative.

Source: RFC 6376 / Google + Yahoo 2024 sender requirements

MTA-STS forces inbound mail to use TLS, preventing downgrade attacks. Requires both a TXT record at _mta-sts.<domain> and a policy file at https://mta-sts.<domain>/.well-known/mta-sts.txt.

Why this matters

Without MTA-STS, inbound mail can be silently downgraded to plain SMTP by a network attacker.

Learn more ▾

MTA-STS (RFC 8461) tells sending mail servers to use TLS and to refuse delivery if TLS fails. Requires both a TXT record at _mta-sts.<domain> AND a policy file at https://mta-sts.<domain>/.well-known/mta-sts.txt. Without it, an active attacker on the network path can strip STARTTLS and read the email in plaintext.

Source: RFC 8461

TLS-RPT (RFC 8460) lets MTAs report TLS-handshake failures, so you can detect and fix MTA-STS misconfigurations. Add a TXT record at _smtp._tls.<domain>.

Why this matters

Without TLS-RPT, you have no visibility into inbound TLS failures — MTA-STS misconfigurations stay hidden until users complain.

Learn more ▾

TLS-RPT (RFC 8460) is the feedback channel for MTA-STS: senders post aggregate reports of TLS-handshake failures to the URI in your _smtp._tls TXT record. Without it, an MTA-STS misconfiguration silently rejects mail and you find out only when someone notices missing email.

Source: RFC 8460

D
Permissions-Policy
Action
No header set
FIX
No header set
Warning::
No Permissions-Policy header
Consider adding a Permissions-Policy header to restrict browser feature access from embedded content.

No Permissions-Policy header set.

Without this header, embedded iframes can request access to sensitive device features.

Suggested header
Permissions-Policy: camera=(), microphone=(), geolocation=(), payment=(), usb=()
B
WAF / Bot Protection
No WAF detected via response headers
REVIEW
No WAF detected via response headers
Info::
No WAF detected
Response headers don't match any known WAF or bot-management product. Sites exposed to abuse (login, signup, payment) typically benefit from a WAF such as Cloudflare, Akamai, AWS WAF, or Imperva.
B
CORS Configuration
No CORS headers
REVIEW
No CORS headers
Info::
No CORS headers present — secure default
CORS Configuration ✓ Secure

No CORS headers detected.

Cross-origin requests are blocked by browser same-origin policy.

Origin reflection test

Some servers mirror the request Origin header, which can be exploited. Test manually:

curl -sI -H "Origin: https://evil.com" <url> | grep -i access-control
B
security.txt
Published with 0 contact(s)
REVIEW

security.txt

A
TLS & Certificates
TLS 1.3, 7 checks passed
PASS
TLS 1.3, 7 checks passed
Info::
TLS 1.3 is used
Got: TLS 1.3
Info::
Strong cipher suite is used
Got: TLS_CHACHA20_POLY1305_SHA256
Info::
HTTP/2 is not negotiated
HTTP/2 provides multiplexing and header compression for better performance.
Got: http/1.1
Info::
OCSP stapling not enabled
Without stapling, the browser performs a separate OCSP roundtrip on first connection -- adding latency and leaking the visited host to the CA. Enable OCSP stapling on your TLS server.
Info::
Certificate is valid (expires in 20 days)
Got: 2026-05-27T19:00:43Z
Warning::
Certificate expires soon (20 days remaining)
Renew the certificate before it expires to avoid browser warnings.
Got: 2026-05-27T19:00:43Z
Info::
Certificate chain has 2 certificates
Info::
Certificate uses modern signature algorithm
Got: ECDSA-SHA384
Info::
Certificate covers 2 domain(s)
Got: *.http3check.net, http3check.net
Info::
Certificate is issued by a trusted CA
Got: CN=E7,O=Let's Encrypt,C=US

Renew the certificate before it expires to avoid browser warnings.

Why this matters

Cert expiry within the renewal window — fix now while there's no user impact, instead of after expiry when there's a full outage.

Learn more ▾

Most CAs recommend renewal at 30 days remaining. Inside that window, schedule the renewal immediately and verify auto-renewal is configured if applicable. Don't wait until 7 days; weekend / holiday timing can leave you exposed.

Source: Let's Encrypt / CA renewal best practice

HTTP/2 provides multiplexing and header compression for better performance.

Why this matters

HTTP/1.1 forces the browser to make sequential requests, multiplying latency on every page.

Learn more ▾

HTTP/2 (and HTTP/3) multiplex many requests over a single connection, eliminating head-of-line blocking. HTTP/1.1 forces the browser to either queue requests or open many parallel connections — both worse. Most modern web servers support HTTP/2 with one config line.

Source: MDN Web Docs

Without stapling, the browser performs a separate OCSP roundtrip on first connection -- adding latency and leaking the visited host to the CA. Enable OCSP stapling on your TLS server.

Why this matters

Without OCSP stapling, every first-time visitor pays an extra OCSP roundtrip — and the CA learns who's visiting your site.

Learn more ▾

OCSP stapling has the server fetch its own revocation status from the CA and attach the signed response to the TLS handshake. Without it, browsers contact the CA directly: extra latency for the user and a privacy leak (the CA sees who connected). Enable ssl_stapling on (nginx) / SSLUseStapling On (Apache) / OCSPStapling = on (Caddy auto-enables).

Source: RFC 6961 / Mozilla Server-Side TLS guide

Connection
Protocol
TLS 1.3
Cipher Suite
TLS_CHACHA20_POLY1305_SHA256
HTTP Version
HTTP/1.1

Certificate Chain

Leaf Certificate
Subject CN=*.http3check.netIssuer CN=E7,O=Let's Encrypt,C=USValid 2026-02-26T19:00:44Z → 2026-05-27T19:00:43ZExpires in 20 days — expiring soon! SANs *.http3check.net, http3check.netSignature ECDSA-SHA384Serial 6bebca11c9237be46b1646986d16e64d7b3
Intermediate (CA Certificate)
Subject CN=E7,O=Let's Encrypt,C=USIssuer CN=ISRG Root X1,O=Internet Security Research Group,C=USValid 2024-03-13T00:00:00Z → 2027-03-12T23:59:59ZExpires in 309 days Signature SHA256-RSASerial aa75f1e62b8f0a220966d38bbfd4baa1
A+
Cookie Security
No cookies set — no cookie security risks
PASS
No cookies set — no cookie security risks
Info::
No cookies set — no cookie security risks

No cookies detected — no cookie security risks to report.

A+
JS Library Vulnerabilities
No known vulnerabilities
PASS
No known vulnerabilities
Info::
No known JavaScript library vulnerabilities detected

No known JavaScript library vulnerabilities detected.

A+
Information Leakage
No exposures
PASS
No exposures
Info::
No security.txt found
Consider adding a security.txt at /.well-known/security.txt.
Info::
No sensitive files exposed

No sensitive files exposed — all paths returned 404.

PathStatusCategoryRisk
/.git/HEAD✓ Not foundVersion Control—
/.git/config✓ Not foundVersion Control—
/.svn/entries✓ Not foundVersion Control—
/.env✓ Not foundConfiguration—
/.env.local✓ Not foundConfiguration—
/.env.production✓ Not foundConfiguration—
/wp-config.php✓ Not foundConfiguration—
/.htaccess✓ Not foundConfiguration—
/phpinfo.php✓ Not foundDebug—
/server-status✓ Not foundDebug—
/server-info✓ Not foundDebug—
/.well-known/security.txt✓ Not foundSecurity Policy—
A
Transport Security
HTTP/3, HSTS, and TLS version analysis
PASS
HTTP/3, HSTS, and TLS version analysis
Info::
HTTP/3 (QUIC) supported
The server advertises HTTP/3 via Alt-Svc for faster connections on mobile networks.
Warning::
Missing Strict-Transport-Security header
HSTS tells browsers to only use HTTPS, preventing SSL stripping attacks.
Info::
TLS 1.3 in use (fastest handshake, 1-RTT)
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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