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Security

· 32 checks — HTTP headers, CSP, TLS handshake, and cookie hygiene rolled into one auditable list.
SCORE
92
GRADE
A
FIX
1
REVIEW
6
PASS
25
INFO
0
Checks
32
25 PASS 6 REVIEW 1 FIX
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
Security Headers
7 of 10 headers properly configured
REVIEW
7 of 10 headers properly configured
Info::
Strict-Transport-Security is properly configured (consider adding preload)
Got: max-age=31536000; includeSubDomains
Info::
X-Content-Type-Options is properly configured
Got: nosniff
Info::
X-Frame-Options is properly configured
Got: DENY
Info::
Referrer-Policy is properly configured
Got: 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=()
Info::
Content-Security-Policy is present
Got: default-src 'self'; script-src 'self'; style-src 'self'; img-src 'self' data:; f…
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 not present
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

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

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

B
Trusted Types (XSS Sink Hardening)
Trusted Types not enabled
REVIEW
Trusted Types not enabled
Info::
Trusted Types not enabled
Trusted Types (CSP3) is a Chrome 83+ defense that requires DOM-XSS sinks (innerHTML, document.write, eval, ...) to receive a typed-and-sanitized value rather than a raw string. Adding `Content-Security-Policy: require-trusted-types-for 'script'; trusted-types default` neutralizes most DOM-XSS even when a payload reaches a sink. Adoption is currently ~0.1% of pages so this is informational; a roll-out usually starts in report-only mode.
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
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
A+
Content Security Policy
8 of 10 CSP checks passed
PASS
8 of 10 CSP checks passed
Info::
Raw CSP policy
Got: default-src 'self'; script-src 'self'; style-src 'self'; img-src 'self' data:; font-src 'self'; connect-src 'none'; form-action 'self'; frame-ancestors 'none'; base-uri 'none'; object-src 'none'
Info::
default-src directive is set
Got: default-src 'self'
Info::
No 'unsafe-inline' in script source
Info::
No 'unsafe-eval' in script source
Info::
No wildcard in script source
Info::
object-src is set to 'none'
Got: object-src 'none'
Info::
base-uri is properly restricted
Got: base-uri 'none'
Info::
frame-ancestors directive is set
Got: frame-ancestors 'none'
Info::
form-action directive is set
Got: form-action 'self'
Info::
upgrade-insecure-requests is not set
This directive upgrades HTTP resources to HTTPS automatically, preventing mixed content.
Expected: upgrade-insecure-requests

This directive upgrades HTTP resources to HTTPS automatically, preventing mixed content.

Expected: upgrade-insecure-requests
Why this matters

Without upgrade-insecure-requests, any HTTP subresource link survives as a mixed-content warning instead of auto-upgrading.

Learn more ▾

Adding `upgrade-insecure-requests` to your CSP turns every http:// subresource fetch into https:// at the browser layer. One-line defense against accidental mixed content from legacy links or third-party widgets.

Source: MDN CSP

Parsed Policy

default-src 'self'
script-src 'self'
style-src 'self'
img-src 'self'data:
font-src 'self'
connect-src 'none'
form-action 'self'
frame-ancestors 'none'
base-uri 'none'
object-src 'none'
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 89 days)
Got: 2026-11-16T19:53:22Z
Info::
Certificate chain has 4 certificates
Info::
Certificate uses modern signature algorithm
Got: ECDSA-SHA384
Info::
Certificate covers 1 domain(s)
Got: strictmx.com
Info::
Certificate is issued by a trusted CA
Got: CN=YE2,O=Let's Encrypt,C=US

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=strictmx.comIssuer CN=YE2,O=Let's Encrypt,C=USValid 2026-08-18T19:53:23Z → 2026-11-16T19:53:22ZExpires in 89 days SANs strictmx.comSignature ECDSA-SHA384Serial 6cd31c969b62d49cc8d3f1722a95aeacf4b
Intermediate (CA Certificate)
Subject CN=YE2,O=Let's Encrypt,C=USIssuer CN=Root YE,O=ISRG,C=USValid 2025-09-03T00:00:00Z → 2028-09-02T23:59:59ZExpires in 745 days Signature ECDSA-SHA384Serial 4df3b15dd6c0784c507cd37b58e6f115
Intermediate (CA Certificate)
Subject CN=Root YE,O=ISRG,C=USIssuer CN=ISRG Root X2,O=Internet Security Research Group,C=USValid 2026-05-13T00:00:00Z → 2032-09-02T23:59:59ZExpires in 2206 days Signature ECDSA-SHA384Serial 872165fc34b6e5fba8add5b3705fb53a
Intermediate (CA Certificate)
Subject CN=ISRG Root X2,O=Internet Security Research Group,C=USIssuer CN=ISRG Root X1,O=Internet Security Research Group,C=USValid 2026-05-13T00:00:00Z → 2032-09-02T23:59:59ZExpires in 2206 days Signature SHA256-RSASerial 6c8f1dc727c7117f7baf853ac980f9cd
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
No new-tab links found -- no tabnabbing surface
PASS
No new-tab links found -- no tabnabbing surface
Info::
No new-tab links present
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+
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
No soft-404 patterns detected in page title or headings
PASS
No soft-404 patterns detected in page title or headings
Info::
No soft-404 patterns detected in page title or headings
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+
Subresource Integrity Adoption
Page has no third-party scripts or stylesheets -- SRI not applicable
PASS
Page has no third-party scripts or stylesheets -- SRI not applicable
Info::
No third-party scripts or stylesheets to protect with SRI
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+
Referrer-Policy Strictness
Referrer-Policy is `strict-origin-when-cross-origin` (modern default -- full URL same-origin, origin-only cross-origin)
PASS
Referrer-Policy is `strict-origin-when-cross-origin` (modern default -- full URL same-origin, origin-only cross-origin)
Info::
Referrer-Policy: `strict-origin-when-cross-origin` -- modern default -- full URL same-origin, origin-only cross-origin
The modern browser default (Chrome 85+, Firefox 87+, Safari 15+). Full URL Referer on same-origin; origin only on cross-origin; no Referer on HTTPS-to-HTTP downgrade. Privacy-safe and breaks no analytics. The recommended explicit value.
Got: strict-origin-when-cross-origin
A+
Source Map Exposure
No source maps accessible (probed 1 candidate URL(s))
PASS
No source maps accessible (probed 1 candidate URL(s))
Info::
No source maps accessible across 1 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+
Subdomain Inventory Exposure
No risky subdomain names in certificate SANs
PASS
No risky subdomain names in certificate SANs
Info::
No risky subdomain names in certificate SANs
A+
Subresource Integrity
No external resources
PASS
No external resources
Info::
No external resources to protect
SRI Coverage No external resources — SRI not applicable
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: reject, SPF: -all, MTA-STS: testing, TLS-RPT
PASS
DMARC: reject, SPF: -all, MTA-STS: testing, TLS-RPT
Info::
DMARC policy is reject — strongest protection
Info::
SPF ends in -all (hard fail) — strongest setting
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 in testing mode
Testing mode reports failures without enforcing the policy. Promote to enforce after monitoring TLS-RPT reports.
Info::
TLS-RPT configured
Got: mailto:postmaster@strictmx.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 reject — strongest protection Record v=DMARC1; p=reject; rua=mailto:postmaster@strictmx.com

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

Testing mode reports failures without enforcing the policy. Promote to enforce after monitoring TLS-RPT reports.

Why this matters

MTA-STS testing mode reports failures but doesn't enforce — your mail is no more protected than without it.

Learn more ▾

Testing mode is for the rollout phase: senders log TLS failures (via TLS-RPT) but still deliver. Once you've reviewed reports and confirmed no legitimate mail is rejected, promote the policy to mode: enforce.

Source: RFC 8461 §5

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))
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.
Info::
HSTS enabled (includeSubDomains)
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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