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Security

· 12 checks — HTTP headers, CSP, TLS handshake, and cookie hygiene rolled into one auditable list.
SCORE
75
GRADE
C
FIX
2
REVIEW
3
PASS
7
INFO
0
Checks
12
7 PASS 3 REVIEW 2 FIX
F
Subresource Integrity
Action
0 of 3 external resources have SRI
FIX
0 of 3 external resources have SRI
Warning::
External link from use.typekit.net lacks integrity attribute
Without SRI, if this CDN is compromised, attackers could inject malicious code.
Got: https://use.typekit.net/fut6uin.css
Warning::
External script from plausible.io lacks integrity attribute
Without SRI, if this CDN is compromised, attackers could inject malicious code.
Got: https://plausible.io/js/script.manual.js
Warning::
External script from cdn.jsdelivr.net lacks integrity attribute
Without SRI, if this CDN is compromised, attackers could inject malicious code.
Got: https://cdn.jsdelivr.net/npm/algoliasearch@4/dist/algoliasearch-lite.umd.js
SRI Coverage 0 / 3 of external resources have integrity hashes
TagDomainIntegrity
<link>use.typekit.net✗ Missing
<script>plausible.io✗ Missing
<script>cdn.jsdelivr.net✗ 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=()
C
Security Headers
Action
6 of 10 headers properly configured
REVIEW
6 of 10 headers properly configured
Info::
Strict-Transport-Security is properly configured
Got: max-age=63072000; includeSubDomains; preload
Info::
X-Content-Type-Options is properly configured
Got: nosniff
Info::
X-Frame-Options is properly configured
Got: 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=()
Info::
Content-Security-Policy is present
Got: default-src 'none'; media-src *; font-src 'self' *.typekit.net *.cloudfront.net …
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: Netlify

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

C
Content Security Policy
Action
6 of 10 CSP checks passed
REVIEW
6 of 10 CSP checks passed
Info::
Raw CSP policy
Got: default-src 'none'; media-src *; font-src 'self' *.typekit.net *.cloudfront.net fonts.gstatic.com data:; img-src * data:; script-src 'self' 'unsafe-inline' 'unsafe-eval' *.google.com *.gstatic.com hackerone.com substackcdn.com static.cloudflareinsights.com js.sentry-cdn.com platform.twitter.com *.substack.com platform.x.com substackapi.com boards.greenhouse.io job-boards.greenhouse.io cdn.jsdelivr.net cdn.optimizely.com *.parsely.com connect.facebook.net info.a16z.com munchkin.marketo.net plausible.io px.ads.linkedin.com snap.licdn.com static.ads-twitter.com www.youtube.com script.crazyegg.com www.google-analytics.com www.googletagmanager.com a16z.com blob:; style-src 'self' 'unsafe-inline' *.netlify.app *.typekit.net fonts.googleapis.com info.a16z.com a16z.com; connect-src *; frame-src 'self' hackerone.com *.google.com platform.twitter.com my.spline.design *.a16z.news *.substack.com *.googletagmanager.com *.loom.com *.cdn.optimizely.com speedrun.substack.com *.simplecast.com gamma.app boards.greenhouse.io job-boards.greenhouse.io www.youtube.com info.a16z.com; base-uri 'none'; form-action 'self' info.a16z.com; frame-ancestors 'self'
Info::
default-src directive is set
Got: default-src 'none'
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 'self' 'unsafe-inline' 'unsafe-eval' *.google.com *.gstatic.com hackerone.com substackcdn.com static.cloudflareinsights.com js.sentry-cdn.com platform.twitter.com *.substack.com platform.x.com substackapi.com boards.greenhouse.io job-boards.greenhouse.io cdn.jsdelivr.net cdn.optimizely.com *.parsely.com connect.facebook.net info.a16z.com munchkin.marketo.net plausible.io px.ads.linkedin.com snap.licdn.com static.ads-twitter.com www.youtube.com script.crazyegg.com www.google-analytics.com www.googletagmanager.com a16z.com blob:
Critical::
'unsafe-eval' found in script source
'unsafe-eval' allows eval() and similar functions, enabling code injection. Remove it.
Got: script-src 'self' 'unsafe-inline' 'unsafe-eval' *.google.com *.gstatic.com hackerone.com substackcdn.com static.cloudflareinsights.com js.sentry-cdn.com platform.twitter.com *.substack.com platform.x.com substackapi.com boards.greenhouse.io job-boards.greenhouse.io cdn.jsdelivr.net cdn.optimizely.com *.parsely.com connect.facebook.net info.a16z.com munchkin.marketo.net plausible.io px.ads.linkedin.com snap.licdn.com static.ads-twitter.com www.youtube.com script.crazyegg.com www.google-analytics.com www.googletagmanager.com a16z.com blob:
Info::
No wildcard in script source
Info::
object-src falls back to default-src
Info::
base-uri is properly restricted
Got: base-uri 'none'
Info::
frame-ancestors directive is set
Got: frame-ancestors 'self'
Info::
form-action directive is set
Got: form-action 'self' info.a16z.com
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

'unsafe-eval' allows eval() and similar functions, enabling code injection. Remove it.

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

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 'none'
media-src *
font-src 'self'*.typekit.net*.cloudfront.netfonts.gstatic.comdata:
img-src *data:
script-src 'self''unsafe-inline''unsafe-eval'*.google.com*.gstatic.comhackerone.comsubstackcdn.comstatic.cloudflareinsights.comjs.sentry-cdn.complatform.twitter.com*.substack.complatform.x.comsubstackapi.comboards.greenhouse.iojob-boards.greenhouse.iocdn.jsdelivr.netcdn.optimizely.com*.parsely.comconnect.facebook.netinfo.a16z.communchkin.marketo.netplausible.iopx.ads.linkedin.comsnap.licdn.comstatic.ads-twitter.comwww.youtube.comscript.crazyegg.comwww.google-analytics.comwww.googletagmanager.coma16z.comblob:
style-src 'self''unsafe-inline'*.netlify.app*.typekit.netfonts.googleapis.cominfo.a16z.coma16z.com
connect-src *
frame-src 'self'hackerone.com*.google.complatform.twitter.commy.spline.design*.a16z.news*.substack.com*.googletagmanager.com*.loom.com*.cdn.optimizely.comspeedrun.substack.com*.simplecast.comgamma.appboards.greenhouse.iojob-boards.greenhouse.iowww.youtube.cominfo.a16z.com
base-uri 'none'
form-action 'self'info.a16z.com
frame-ancestors 'self'
C
CORS Configuration
Action
Origin: *
REVIEW
Origin: *
Info::
Access-Control-Allow-Origin: * — unrestricted
Any website can read this resource's response. Appropriate for public APIs but not for user-specific content.
Info::
Origin reflection not testable with a single request
Some servers reflect the request Origin header. This requires manual testing with a crafted Origin header.
CORS Configuration Permissive
Allow-Origin *

Any website can read responses from this resource.

HeaderValueStatus
Access-Control-Allow-Origin*⚠

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 75 days)
Got: 2026-07-07T03:54:26Z
Info::
Certificate chain has 2 certificates
Info::
Certificate uses modern signature algorithm
Got: ECDSA-SHA384
Info::
Certificate covers 2 domain(s)
Got: a16z.com, www.a16z.com
Info::
Certificate is issued by a trusted CA
Got: CN=E7,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

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

Certificate Chain

Leaf Certificate
Subject CN=a16z.comIssuer CN=E7,O=Let's Encrypt,C=USValid 2026-04-08T03:54:27Z → 2026-07-07T03:54:26ZExpires in 75 days SANs a16z.com, www.a16z.comSignature ECDSA-SHA384Serial 6b474871a709c4d33a1c536bc7f5e21d445
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 324 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::
security.txt is present — good practice
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✗ ExposedSecurity PolicyInfo
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; pct=100; sp=reject; rua=mailto:21zezn4c@ag.dmarcian.com; ruf=mailto:21zezn4c@fr.dmarcian.com
A+
security.txt
Signed, 1 contact(s) — RFC 9116 compliant
PASS

security.txt

Contact: mailto:cirt@a16z.com
Expires: 2027-07-15T00:00:00.000Z
Encryption: https://a16z.com/pgp-key.txt
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 (includeSubDomains, preload)
Info::
HSTS preload enabled
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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