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Security

· 12 checks — HTTP headers, CSP, TLS handshake, and cookie hygiene rolled into one auditable list.
SCORE
71
GRADE
C
FIX
4
REVIEW
2
PASS
6
INFO
0
Checks
12
6 PASS 2 REVIEW 4 FIX
D
Content Security Policy
Action
4 of 10 CSP checks passed
FIX
4 of 10 CSP checks passed
Info::
Raw CSP policy
Got: script-src 'sha256-zBlbZesIuEAhZbkCazQIPdIka9RR1ISKJw71N/rBa8E=' 'nonce-awchvhF3upmTQjgEbVinVw==' 'self' 'unsafe-inline' https://note.com https://frontend.st-note.com https://d291vdycu0ht11.cloudfront.net https://d2l930y2yx77uc.cloudfront.net https://cdn.st-note.com https://www.googletagmanager.com https://www.google-analytics.com https://www.googleanalytics.com https://www.googleoptimize.com https://optimize.google.com https://*.facebook.net https://*.instagram.com https://platform.twitter.com https://*.twimg.com cdn.iframe.ly https://cdn.embedly.com https://*.tiktok.com https://*.tiktokcdn.com https://*.ibytedtos.com https://speakerdeck.com https://*.flickr.com https://*.mul-pay.jp https://stage-travel.fraudprevention.jp https://travel.fraudprevention.jp https://www.datadoghq-browser-agent.com http://cloudfront.loggly.com https://*.ttwstatic.com https://www.google.com/recaptcha/ https://www.gstatic.com/recaptcha/ https://assets.kurashiru.com/ https://*.hsadspixel.net https://*.hs-analytics.net https://js.hscta.net https://*.hubspot.com https://static.hsappstatic.net https://*.usemessages.com https://*.hs-banner.com https://*.hubspotusercontent00.net https://*.hubspotusercontent10.net https://*.hubspotusercontent20.net https://*.hubspotusercontent30.net https://*.hubspotusercontent40.net https://*.hubspot.net https://*.hscollectedforms.net https://*.hsleadflows.net https://*.hsforms.net https://*.hsforms.com https://*.hs-scripts.com https://*.hubspotfeedback.com https://feedback.hubapi.com https://static.ads-twitter.com https://static.paypay.ne.jp https://static-fe.payments-amazon.com https://embed.bsky.app/static/embed.js https://sdk.immedio.io; object-src 'none'; base-uri 'self'
Warning::
default-src directive is missing
default-src provides a fallback for other directives. Set it to restrict default resource loading.
Expected: default-src 'self'
Critical::
'unsafe-inline' found in script source
'unsafe-inline' allows inline <script> tags, defeating CSP against XSS. Remove it and use nonces or hashes instead.
Got: script-src 'sha256-zBlbZesIuEAhZbkCazQIPdIka9RR1ISKJw71N/rBa8E=' 'nonce-awchvhF3upmTQjgEbVinVw==' 'self' 'unsafe-inline' https://note.com https://frontend.st-note.com https://d291vdycu0ht11.cloudfront.net https://d2l930y2yx77uc.cloudfront.net https://cdn.st-note.com https://www.googletagmanager.com https://www.google-analytics.com https://www.googleanalytics.com https://www.googleoptimize.com https://optimize.google.com https://*.facebook.net https://*.instagram.com https://platform.twitter.com https://*.twimg.com cdn.iframe.ly https://cdn.embedly.com https://*.tiktok.com https://*.tiktokcdn.com https://*.ibytedtos.com https://speakerdeck.com https://*.flickr.com https://*.mul-pay.jp https://stage-travel.fraudprevention.jp https://travel.fraudprevention.jp https://www.datadoghq-browser-agent.com http://cloudfront.loggly.com https://*.ttwstatic.com https://www.google.com/recaptcha/ https://www.gstatic.com/recaptcha/ https://assets.kurashiru.com/ https://*.hsadspixel.net https://*.hs-analytics.net https://js.hscta.net https://*.hubspot.com https://static.hsappstatic.net https://*.usemessages.com https://*.hs-banner.com https://*.hubspotusercontent00.net https://*.hubspotusercontent10.net https://*.hubspotusercontent20.net https://*.hubspotusercontent30.net https://*.hubspotusercontent40.net https://*.hubspot.net https://*.hscollectedforms.net https://*.hsleadflows.net https://*.hsforms.net https://*.hsforms.com https://*.hs-scripts.com https://*.hubspotfeedback.com https://feedback.hubapi.com https://static.ads-twitter.com https://static.paypay.ne.jp https://static-fe.payments-amazon.com https://embed.bsky.app/static/embed.js https://sdk.immedio.io
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 'self'
Warning::
frame-ancestors directive is missing
frame-ancestors controls who can embed your page, preventing clickjacking. Set it to 'self' or 'none'.
Expected: frame-ancestors 'self'
Warning::
form-action directive is missing
form-action restricts where forms can submit data, preventing form hijacking.
Expected: 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

'unsafe-inline' allows inline <script> tags, defeating CSP against XSS. Remove it and use nonces or hashes instead.

Why this matters

Unsafe value (unsafe-inline, unsafe-eval) in script-src defeats CSP's main protection — XSS injections can execute again.

Learn more ▾

unsafe-inline allows inline <script> tags; unsafe-eval allows eval() and similar. Both are necessary for some legacy code but explicitly dangerous. Migrate to nonces (per-page random tokens) or hashes (per-script SHA-256) instead.

Source: OWASP CSP / MDN

default-src provides a fallback for other directives. Set it to restrict default resource loading.

Expected: default-src 'self'
Why this matters

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

frame-ancestors controls who can embed your page, preventing clickjacking. Set it to 'self' or 'none'.

Expected: frame-ancestors 'self'
Why this matters

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

form-action restricts where forms can submit data, preventing form hijacking.

Expected: form-action 'self'
Why this matters

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

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

script-src 'sha256-zBlbZesIuEAhZbkCazQIPdIka9RR1ISKJw71N/rBa8E=''nonce-awchvhF3upmTQjgEbVinVw==''self''unsafe-inline'https://note.comhttps://frontend.st-note.comhttps://d291vdycu0ht11.cloudfront.nethttps://d2l930y2yx77uc.cloudfront.nethttps://cdn.st-note.comhttps://www.googletagmanager.comhttps://www.google-analytics.comhttps://www.googleanalytics.comhttps://www.googleoptimize.comhttps://optimize.google.comhttps://*.facebook.nethttps://*.instagram.comhttps://platform.twitter.comhttps://*.twimg.comcdn.iframe.lyhttps://cdn.embedly.comhttps://*.tiktok.comhttps://*.tiktokcdn.comhttps://*.ibytedtos.comhttps://speakerdeck.comhttps://*.flickr.comhttps://*.mul-pay.jphttps://stage-travel.fraudprevention.jphttps://travel.fraudprevention.jphttps://www.datadoghq-browser-agent.comhttp://cloudfront.loggly.comhttps://*.ttwstatic.comhttps://www.google.com/recaptcha/https://www.gstatic.com/recaptcha/https://assets.kurashiru.com/https://*.hsadspixel.nethttps://*.hs-analytics.nethttps://js.hscta.nethttps://*.hubspot.comhttps://static.hsappstatic.nethttps://*.usemessages.comhttps://*.hs-banner.comhttps://*.hubspotusercontent00.nethttps://*.hubspotusercontent10.nethttps://*.hubspotusercontent20.nethttps://*.hubspotusercontent30.nethttps://*.hubspotusercontent40.nethttps://*.hubspot.nethttps://*.hscollectedforms.nethttps://*.hsleadflows.nethttps://*.hsforms.nethttps://*.hsforms.comhttps://*.hs-scripts.comhttps://*.hubspotfeedback.comhttps://feedback.hubapi.comhttps://static.ads-twitter.comhttps://static.paypay.ne.jphttps://static-fe.payments-amazon.comhttps://embed.bsky.app/static/embed.jshttps://sdk.immedio.io
object-src 'none'
base-uri 'self'
F
Subresource Integrity
Action
0 of 15 external resources have SRI
FIX
0 of 15 external resources have SRI
Warning::
External script from frontend.st-note.com lacks integrity attribute
Without SRI, if this CDN is compromised, attackers could inject malicious code.
Got: https://frontend.st-note.com/nuxt/production/note.fad95c4b18431a424903.js
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/gtag/js?id=UA-48687000-1
Warning::
External script from frontend.st-note.com lacks integrity attribute
Without SRI, if this CDN is compromised, attackers could inject malicious code.
Got: https://frontend.st-note.com/nuxt/production/7a20741.modern.js
Warning::
External script from frontend.st-note.com lacks integrity attribute
Without SRI, if this CDN is compromised, attackers could inject malicious code.
Got: https://frontend.st-note.com/nuxt/production/note.bc60adde6d5594130455.js
Warning::
External script from frontend.st-note.com lacks integrity attribute
Without SRI, if this CDN is compromised, attackers could inject malicious code.
Got: https://frontend.st-note.com/nuxt/production/note.20610ddd0dd06ba64052.js
Warning::
External script from frontend.st-note.com lacks integrity attribute
Without SRI, if this CDN is compromised, attackers could inject malicious code.
Got: https://frontend.st-note.com/nuxt/production/note.13106bb050f1b35b2a97.js
Warning::
External script from frontend.st-note.com lacks integrity attribute
Without SRI, if this CDN is compromised, attackers could inject malicious code.
Got: https://frontend.st-note.com/nuxt/production/note.b63caa39a132415a2726.js
Warning::
External script from frontend.st-note.com lacks integrity attribute
Without SRI, if this CDN is compromised, attackers could inject malicious code.
Got: https://frontend.st-note.com/nuxt/production/note.6b7e04e01860eee2d9ae.js
Warning::
External script from frontend.st-note.com lacks integrity attribute
Without SRI, if this CDN is compromised, attackers could inject malicious code.
Got: https://frontend.st-note.com/nuxt/production/note.15ab7f5febc8bfbec1f4.js
Warning::
External script from frontend.st-note.com lacks integrity attribute
Without SRI, if this CDN is compromised, attackers could inject malicious code.
Got: https://frontend.st-note.com/nuxt/production/note.c91878598083364e2527.js
Warning::
External script from frontend.st-note.com lacks integrity attribute
Without SRI, if this CDN is compromised, attackers could inject malicious code.
Got: https://frontend.st-note.com/nuxt/production/note.4ccd03c3254aa4e4de00.js
Warning::
External script from frontend.st-note.com lacks integrity attribute
Without SRI, if this CDN is compromised, attackers could inject malicious code.
Got: https://frontend.st-note.com/nuxt/production/note.adee14e96f8f93858223.js
Warning::
External script from frontend.st-note.com lacks integrity attribute
Without SRI, if this CDN is compromised, attackers could inject malicious code.
Got: https://frontend.st-note.com/nuxt/production/note.d9476e5d2ea2f8af7fe1.js
Warning::
External script from frontend.st-note.com lacks integrity attribute
Without SRI, if this CDN is compromised, attackers could inject malicious code.
Got: https://frontend.st-note.com/nuxt/production/note.c614ca4ad5477502611f.js
Warning::
External script from frontend.st-note.com lacks integrity attribute
Without SRI, if this CDN is compromised, attackers could inject malicious code.
Got: https://frontend.st-note.com/nuxt/production/note.fdac0c03aed0f6da2e2f.js
SRI Coverage 0 / 15 of external resources have integrity hashes
TagDomainIntegrity
<script>frontend.st-note.com✗ Missing
<script>www.googletagmanager.com✗ Missing
<script>frontend.st-note.com✗ Missing
<script>frontend.st-note.com✗ Missing
<script>frontend.st-note.com✗ Missing
<script>frontend.st-note.com✗ Missing
<script>frontend.st-note.com✗ Missing
<script>frontend.st-note.com✗ Missing
<script>frontend.st-note.com✗ Missing
<script>frontend.st-note.com✗ Missing
<script>frontend.st-note.com✗ Missing
<script>frontend.st-note.com✗ Missing
<script>frontend.st-note.com✗ Missing
<script>frontend.st-note.com✗ Missing
<script>frontend.st-note.com✗ 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=()
D
security.txt
Action
No /.well-known/security.txt published
FIX

security.txt

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

C
Security Headers
Action
5 of 10 headers properly configured
REVIEW
5 of 10 headers properly configured
Warning::
HSTS is missing includeSubDomains
Without includeSubDomains, subdomains can still be accessed over HTTP.
Got: max-age=31536000 Expected: max-age=31536000; includeSubDomains
Info::
X-Content-Type-Options is properly configured
Got: nosniff
Info::
X-Frame-Options is properly configured
Got: SAMEORIGIN
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=()
Info::
Content-Security-Policy is present
Got: script-src 'sha256-zBlbZesIuEAhZbkCazQIPdIka9RR1ISKJw71N/rBa8E=' 'nonce-awchvhF3…
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

Without includeSubDomains, subdomains can still be accessed over HTTP.

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

Without includeSubDomains, a forgotten dev subdomain over HTTP can set malicious cookies that ride to the apex.

Learn more ▾

HSTS without includeSubDomains protects only the exact domain. Cookies set on a non-HSTS subdomain can ride to the apex via cookie-scope attacks. The fix is one directive append. Verify all subdomains support HTTPS first — adding includeSubDomains to a domain with HTTP-only subdomains breaks them.

Source: RFC 6797

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

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+
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::
Certificate is valid (expires in 228 days)
Got: 2026-12-06T07:45:42Z
Info::
Certificate chain has 2 certificates
Info::
Certificate uses modern signature algorithm
Got: SHA256-RSA
Info::
Certificate covers 2 domain(s)
Got: *.note.com, note.com
Info::
Certificate is issued by a trusted CA
Got: CN=GlobalSign GCC R3 DV TLS CA 2020,O=GlobalSign nv-sa,C=BE

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

Connection
Protocol
TLS 1.3
Cipher Suite
TLS_AES_128_GCM_SHA256
HTTP Version
HTTP/1.1

Certificate Chain

Leaf Certificate
Subject CN=*.note.comIssuer CN=GlobalSign GCC R3 DV TLS CA 2020,O=GlobalSign nv-sa,C=BEValid 2025-11-04T07:45:43Z → 2026-12-06T07:45:42ZExpires in 228 days SANs *.note.com, note.comSignature SHA256-RSASerial 63eb318856ca9993c5a4abf4
Intermediate (CA Certificate)
Subject CN=GlobalSign GCC R3 DV TLS CA 2020,O=GlobalSign nv-sa,C=BEIssuer CN=GlobalSign,OU=GlobalSign Root CA - R3,O=GlobalSignValid 2020-07-28T00:00:00Z → 2029-03-18T00:00:00ZExpires in 1061 days Signature SHA256-RSASerial 77bd0e0742d5d9e9d049d774d02a6f9a
A+
Cookie Security
1 cookies analyzed, 2 checks passed
PASS
1 cookies analyzed, 2 checks passed
Info::
Cookie '_note_session_v5' has the Secure flag
Info::
Cookie '_note_session_v5' has the HttpOnly flag
Warning::
Cookie '_note_session_v5' has no SameSite attribute
Without an explicit SameSite attribute, browser default behavior varies. Set SameSite=Lax or Strict.
1 cookies analyzed 1 warnings
NameSecureHttpOnlySameSiteSizeIssues
_note_session_v5✓✓—48 B1
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
Email Security
DMARC: quarantine
PASS
DMARC: quarantine
Info::
DMARC policy is quarantine — good protection
DMARC
Policy quarantine — good protection Record v=DMARC1;p=quarantine;rua=mailto:dmarc-reports@note.jp;fo=1
A
Transport Security
HTTP/3, HSTS, and TLS version analysis
PASS
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.
Info::
HSTS enabled (base policy)
Info::
HSTS missing includeSubDomains
Without includeSubDomains, HSTS only protects the exact domain.
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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