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Security

· 32 checks — HTTP headers, CSP, TLS handshake, and cookie hygiene rolled into one auditable list.
SCORE
81
GRADE
B
FIX
5
REVIEW
7
PASS
20
INFO
0
Checks
32
20 PASS 7 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: Apache
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 Adoption
Action
0% SRI adoption (0/2 third-party resources)
FIX
0% SRI adoption (0/2 third-party resources)
Warning::
SRI adoption: 0/2 third-party resources protected (0%)
Of 2 third-party `<script>` / `<link rel=stylesheet>` resources, 0 (0%) declare a Subresource Integrity hash via the `integrity=` attribute. SRI binds the page to the exact bytes of the third-party resource: if the CDN is compromised, attacker-modified bytes won't match the declared hash and the browser refuses to execute the resource. Missing SRI on (first 2 examples): - https://analytics.diehl.com/js/container_44dHNPNt.js - https://cdn.cookielaw.org/scripttemplates/otSDKStub.js Fix: add `integrity="sha384-..."` and `crossorigin="anonymous"` attributes. Generators: srihash.org, or in-browser via `await crypto.subtle.digest('SHA-384', bytes)`. Cache-bust the resource URL when you change versions, since the integrity hash will mismatch with old cached bytes.
Got: 0% (0/2)
F
Subresource Integrity
Action
0 of 2 external resources have SRI
FIX
0 of 2 external resources have SRI
Warning::
External script from analytics.diehl.com lacks integrity attribute
Without SRI, if this CDN is compromised, attackers could inject malicious code.
Got: https://analytics.diehl.com/js/container_44dHNPNt.js
Warning::
External script from cdn.cookielaw.org lacks integrity attribute
Without SRI, if this CDN is compromised, attackers could inject malicious code.
Got: https://cdn.cookielaw.org/scripttemplates/otSDKStub.js
SRI Coverage 0 / 2 of external resources have integrity hashes
TagDomainIntegrity
<script>analytics.diehl.com✗ Missing
<script>cdn.cookielaw.org✗ Missing
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.
C
security.txt
Action
No security.txt file found
REVIEW
No security.txt file found
Info::
No security.txt file found
security.txt (RFC 9116) provides a standardized way for security researchers to report vulnerabilities. Create one at /.well-known/security.txt with at least a Contact field.
Expected: /.well-known/security.txt

security.txt

No security.txt found at /.well-known/security.txt

C
Permissions-Policy Granularity
Action
No Permissions-Policy header set -- powerful features (camera / microphone / geolocation / payment / USB) default to allow-on-same-origin
REVIEW
No Permissions-Policy header set -- powerful features (camera / microphone / geolocation / payment / USB) default to allow-on-same-origin
Warning::
Permissions-Policy header not set -- features default to allow-on-same-origin
Without a `Permissions-Policy` (or legacy `Feature-Policy`) header, every powerful browser feature defaults to its spec default policy (typically `self`). A third-party iframe injected via XSS or a misconfigured embed can still request access to the user's camera, microphone, geolocation, payment APIs, USB devices, etc. Explicitly deny features the page doesn't need: ``` Permissions-Policy: camera=(), microphone=(), geolocation=(), payment=(), usb=(), accelerometer=(), gyroscope=() ``` Features the page legitimately uses can stay enabled with `feature=(self)`.
Got: header absent
B
Referrer-Policy Strictness
Referrer-Policy header not set -- browser default applies (modern: strict-origin-when-cross-origin; legacy browsers: no-referrer-when-downgrade)
REVIEW
Referrer-Policy header not set -- browser default applies (modern: strict-origin-when-cross-origin; legacy browsers: no-referrer-when-downgrade)
Info::
Referrer-Policy header not set -- browser default applies
Without an explicit `Referrer-Policy` header, the browser falls back to its default policy. Modern browsers (Chrome 85+, Firefox 87+, Safari 15+) default to `strict-origin-when-cross-origin`, which is privacy-safe. Legacy browsers default to the leaky `no-referrer-when-downgrade`, which sends the full URL (including path + query) on cross-origin HTTPS-to-HTTPS requests. Set an explicit header to ensure consistent behavior: ``` Referrer-Policy: strict-origin-when-cross-origin ``` This matches the modern browser default and is privacy-safe without breaking referrer-based same-origin analytics.
Got: header absent
C
Subdomain Inventory Exposure
Action
3 risky subdomain name(s) in certificate SANs
REVIEW
3 risky subdomain name(s) in certificate SANs
Warning::
3 risky subdomain name(s) advertised in certificate SANs
These names are publicly visible via Certificate Transparency logs (crt.sh, censys.io) -- any attacker can enumerate them in seconds. Operators are often unaware that internal/staging/admin endpoints are inadvertently advertised this way. Mitigation: use a wildcard cert that doesn't enumerate, issue per-environment certs without non-prod SANs on the prod cert, or move internal services to private DNS off the public cert.
Got: qa.microsite.diehl.com, qa.preview.diehl.com, qa.www.diehl.com
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
Transport Security
HTTP/3, HSTS, and TLS version analysis
REVIEW
HTTP/3, HSTS, and TLS version analysis
Info::
HTTP/3 (QUIC) not advertised
HTTP/3 eliminates head-of-line blocking. If your CDN supports it, consider enabling it.
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)
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_AES_128_GCM_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 50 days)
Got: 2026-07-06T23:59:59Z
Info::
Certificate chain has 3 certificates
Info::
Certificate uses modern signature algorithm
Got: SHA384-RSA
Info::
Certificate covers 10 domain(s)
Got: www.diehl.com, diehl.com, microsite.diehl.com, mta-sts.diehl.com, news2go.diehl.com, preview.diehl.com, preview.microsite.diehl.com, qa.microsite.diehl.com, qa.preview.diehl.com, qa.www.diehl.com
Info::
Certificate is issued by a trusted CA
Got: CN=Sectigo Public Server Authentication CA DV R36,O=Sectigo Limited,C=GB

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_AES_128_GCM_SHA256
HTTP Version
HTTP/1.1

Certificate Chain

Leaf Certificate
Subject CN=www.diehl.comIssuer CN=Sectigo Public Server Authentication CA DV R36,O=Sectigo Limited,C=GBValid 2025-06-05T00:00:00Z → 2026-07-06T23:59:59ZExpires in 50 days SANs www.diehl.com, diehl.com, microsite.diehl.com, mta-sts.diehl.com, news2go.diehl.com, preview.diehl.com, preview.microsite.diehl.com, qa.microsite.diehl.com, qa.preview.diehl.com, qa.www.diehl.comSignature SHA384-RSASerial f5ab5b4b109f39b2b8e871e66ec9a042
Intermediate (CA Certificate)
Subject CN=Sectigo Public Server Authentication CA DV R36,O=Sectigo Limited,C=GBIssuer CN=Sectigo Public Server Authentication Root R46,O=Sectigo Limited,C=GBValid 2021-03-22T00:00:00Z → 2036-03-21T23:59:59ZExpires in 3596 days Signature SHA384-RSASerial 397a66cc2756362e0daa87ca6eabe3b1
Intermediate (CA Certificate)
Subject CN=Sectigo Public Server Authentication Root R46,O=Sectigo Limited,C=GBIssuer CN=USERTrust RSA Certification Authority,O=The USERTRUST Network,L=Jersey City,ST=New Jersey,C=USValid 2021-03-22T00:00:00Z → 2038-01-18T23:59:59ZExpires in 4264 days Signature SHA384-RSASerial d27fbbc1de359e5216ad6149586099c4
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+
Cross-Origin Tab Safety
All 7 new-tab link(s) carry rel=noopener
PASS
All 7 new-tab link(s) carry rel=noopener
Info::
All 7 new-tab link(s) carry rel=noopener
A+
CSP Inline-Style Readiness
No inline style attributes -- strict CSP is feasible
PASS
No inline style attributes -- strict CSP is feasible
Info::
No inline style attributes detected
A+
Trusted Types (XSS Sink Hardening)
No CSP header -- Trusted Types check is N/A
PASS
No CSP header -- Trusted Types check is N/A
Info::
No CSP header found -- Trusted Types check is N/A
A+
Bot Challenge Detection
Scan reached real page content (no bot-protection interstitial)
PASS
Scan reached real page content (no bot-protection interstitial)
Info::
No bot-protection interstitial detected -- the rest of the report reflects the real page
A+
Soft-404 Detection
HTTP status is non-2xx -- soft-404 check is N/A
PASS
HTTP status is non-2xx -- soft-404 check is N/A
Info::
HTTP status is non-2xx -- soft-404 check is N/A
A+
Empty Page Detection
Page has substantive body text and no placeholder / template-leak signals
PASS
Page has substantive body text and no placeholder / template-leak signals
Info::
Page has substantive body text and no placeholder / template-leak signals
A+
Geo-Restriction Detection
No geo-restriction signals detected -- scan reached the page from an allowed region
PASS
No geo-restriction signals detected -- scan reached the page from an allowed region
Info::
No geo-restriction detected
A+
Maintenance Mode Detection
No maintenance-mode signals detected -- scan reached a normal page
PASS
No maintenance-mode signals detected -- scan reached a normal page
Info::
No maintenance-mode signals detected
A+
CORS Depth
No CORS response headers -- the resource is same-origin-only by browser default
PASS
No CORS response headers -- the resource is same-origin-only by browser default
Info::
No CORS response headers -- the resource is same-origin-only by browser default
A+
Source Map Exposure
No source maps accessible (probed 5 candidate URL(s))
PASS
No source maps accessible (probed 5 candidate URL(s))
Info::
No source maps accessible across 5 probed candidate(s)
A+
HTML Version Disclosure
No software-version disclosures in HTML
PASS
No software-version disclosures in HTML
Info::
No software-version disclosures in HTML
A+
Open Redirect Surface
No redirect-shaped query parameters in DOM links
PASS
No redirect-shaped query parameters in DOM links
Info::
No redirect-shaped query parameters in DOM links
A+
Auth Security
Page is not a login form -- auth-security checks are N/A
PASS
Page is not a login form -- auth-security checks are N/A
Info::
Page does not appear to be a login form
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—
/package.json✓ Not founddependency-manifest—
/composer.json✓ Not founddependency-manifest—
/Gemfile✓ Not founddependency-manifest—
/Gemfile.lock✓ Not founddependency-manifest—
/requirements.txt✓ Not founddependency-manifest—
/pom.xml✓ Not founddependency-manifest—
/.gitlab-ci.yml✓ Not foundci-config—
/.travis.yml✓ Not foundci-config—
A+
Email Security
DMARC: quarantine, SPF: -all, DKIM, MTA-STS: enforce, TLS-RPT
PASS
DMARC: quarantine, SPF: -all, DKIM, MTA-STS: enforce, TLS-RPT
Info::
DMARC policy is quarantine — good protection
Info::
SPF ends in -all (hard fail) — strongest setting
Info::
DKIM configured (selectors: default)
Info::
MTA-STS in enforce mode - inbound mail protected
Info::
TLS-RPT configured
Got: mailto:postmaster@diehl.com
Info::
BIMI not configured
BIMI (Brand Indicators for Message Identification) lets supporting clients (Gmail, Apple Mail, Yahoo) display your verified logo next to your messages. Optional but raises trust signals. Requires DMARC at p=quarantine or p=reject to be honored.
DMARC
Policy quarantine — good protection Record v=DMARC1; p=quarantine; rua=mailto:DMARC-feedback@diehl.com; ruf=mailto:DMARC-forensic-reports@diehl.com; adkim=r; aspf=r; rf=afrf; pct=100

BIMI (Brand Indicators for Message Identification) lets supporting clients (Gmail, Apple Mail, Yahoo) display your verified logo next to your messages. Optional but raises trust signals. Requires DMARC at p=quarantine or p=reject to be honored.

Why this matters

Security gaps expose your site and users to attacks, eroding trust.

A+
API Surface
No API specs or GraphQL introspection found (probed 11 candidate path(s))
PASS
No API specs or GraphQL introspection found (probed 11 candidate path(s))
Info::
No API specs or GraphQL introspection found (probed 11 path(s))
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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