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Security

· 13 checks — HTTP headers, CSP, TLS handshake, and cookie hygiene rolled into one auditable list.
SCORE
68
GRADE
D
FIX
6
REVIEW
2
PASS
5
INFO
0
Checks
13
5 PASS 2 REVIEW 6 FIX
D
Security Headers
Action
4 of 10 headers properly configured
FIX
4 of 10 headers properly configured
Warning::
HSTS is missing includeSubDomains
Without includeSubDomains, subdomains can still be accessed over HTTP.
Got: max-age=631138519 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
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: default-src 'self' d2kfnvwohu0503.cloudfront.net staticinstapaper.s3.amazonaws.c…
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: InstapaperServer

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

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

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

F
Content Security Policy
Action
3 of 10 CSP checks passed
FIX
3 of 10 CSP checks passed
Info::
Raw CSP policy
Got: default-src 'self' d2kfnvwohu0503.cloudfront.net staticinstapaper.s3.amazonaws.com staticinstapaper.s3.dualstack.us-west-2.amazonaws.com;script-src 'self' 'nonce-gxrqCWPOAk' 'strict-dynamic' 'unsafe-inline' 'unsafe-eval' js.stripe.com d2kfnvwohu0503.cloudfront.net staticinstapaper.s3.amazonaws.com staticinstapaper.s3.dualstack.us-west-2.amazonaws.com use.typekit.net www.google-analytics.com www.google.com www.gstatic.com cdn.carbonads.com srv.carbonads.net;font-src 'self' d2kfnvwohu0503.cloudfront.net staticinstapaper.s3.amazonaws.com staticinstapaper.s3.dualstack.us-west-2.amazonaws.com *.typekit.net netdna.bootstrapcdn.com;style-src 'self' netdna.bootstrapcdn.com d2kfnvwohu0503.cloudfront.net staticinstapaper.s3.amazonaws.com staticinstapaper.s3.dualstack.us-west-2.amazonaws.com 'unsafe-inline';connect-src 'self' *.carbonads.net carbonads.net js.stripe.com www.google-analytics.com;frame-src 'self' js.stripe.com *.youtube.com youtube.com *.vimeo.com vimeo.com www.google.com ifttt.com embed.instapaper.com;img-src * data:;
Info::
default-src directive is set
Got: default-src 'self' d2kfnvwohu0503.cloudfront.net staticinstapaper.s3.amazonaws.com staticinstapaper.s3.dualstack.us-west-2.amazonaws.com
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' 'nonce-gxrqCWPOAk' 'strict-dynamic' 'unsafe-inline' 'unsafe-eval' js.stripe.com d2kfnvwohu0503.cloudfront.net staticinstapaper.s3.amazonaws.com staticinstapaper.s3.dualstack.us-west-2.amazonaws.com use.typekit.net www.google-analytics.com www.google.com www.gstatic.com cdn.carbonads.com srv.carbonads.net
Critical::
'unsafe-eval' found in script source
'unsafe-eval' allows eval() and similar functions, enabling code injection. Remove it.
Got: script-src 'self' 'nonce-gxrqCWPOAk' 'strict-dynamic' 'unsafe-inline' 'unsafe-eval' js.stripe.com d2kfnvwohu0503.cloudfront.net staticinstapaper.s3.amazonaws.com staticinstapaper.s3.dualstack.us-west-2.amazonaws.com use.typekit.net www.google-analytics.com www.google.com www.gstatic.com cdn.carbonads.com srv.carbonads.net
Info::
No wildcard in script source
Info::
object-src falls back to default-src
Warning::
base-uri directive is missing
Without base-uri, attackers can inject a <base> tag to hijack relative URLs. Set it to 'self' or 'none'.
Expected: 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

'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

Without base-uri, attackers can inject a <base> tag to hijack relative URLs. Set it to 'self' or 'none'.

Expected: base-uri 'self'
Why this matters

Missing base-uri in CSP leaves a base-tag injection attack path open even on otherwise strict policies.

Learn more ▾

A common omission: developers add CSP for script-src and frame-ancestors but forget base-uri. The result is a CSP that looks strict but lets an attacker rewrite every URL on the page via <base href>. Add `base-uri 'self'` to close the gap.

Source: MDN CSP

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

default-src 'self'd2kfnvwohu0503.cloudfront.netstaticinstapaper.s3.amazonaws.comstaticinstapaper.s3.dualstack.us-west-2.amazonaws.com
script-src 'self''nonce-gxrqCWPOAk''strict-dynamic''unsafe-inline''unsafe-eval'js.stripe.comd2kfnvwohu0503.cloudfront.netstaticinstapaper.s3.amazonaws.comstaticinstapaper.s3.dualstack.us-west-2.amazonaws.comuse.typekit.netwww.google-analytics.comwww.google.comwww.gstatic.comcdn.carbonads.comsrv.carbonads.net
font-src 'self'd2kfnvwohu0503.cloudfront.netstaticinstapaper.s3.amazonaws.comstaticinstapaper.s3.dualstack.us-west-2.amazonaws.com*.typekit.netnetdna.bootstrapcdn.com
style-src 'self'netdna.bootstrapcdn.comd2kfnvwohu0503.cloudfront.netstaticinstapaper.s3.amazonaws.comstaticinstapaper.s3.dualstack.us-west-2.amazonaws.com'unsafe-inline'
connect-src 'self'*.carbonads.netcarbonads.netjs.stripe.comwww.google-analytics.com
frame-src 'self'js.stripe.com*.youtube.comyoutube.com*.vimeo.comvimeo.comwww.google.comifttt.comembed.instapaper.com
img-src *data:
D
Subresource Integrity
Action
1 of 10 external resources have SRI
FIX
1 of 10 external resources have SRI
Info::
script from www.gstatic.com has SRI protection
Warning::
External script from use.typekit.net lacks integrity attribute
Without SRI, if this CDN is compromised, attackers could inject malicious code.
Got: //use.typekit.net/any5kzc.js
Warning::
External script from d2kfnvwohu0503.cloudfront.net lacks integrity attribute
Without SRI, if this CDN is compromised, attackers could inject malicious code.
Got: https://d2kfnvwohu0503.cloudfront.net/js/vendor.min.js?v=92c177972ce291dec04ec903f691c3925c98292d443820a6cb3eb774e4c1363795dcae3fd7d416e9851999d33538c959de1fe2ebc0725d68104bd0b5b87a195c
Warning::
External script from d2kfnvwohu0503.cloudfront.net lacks integrity attribute
Without SRI, if this CDN is compromised, attackers could inject malicious code.
Got: https://d2kfnvwohu0503.cloudfront.net/js/main.min.js?v=a949851f0a8ee625a7893857b94481360a89b154e60968cdfb2667342b6c89a6ab056d6f7c74759325085c4b84aebb6b3f6044e949fbf3ad737469058a05f0d5
Warning::
External link from d2kfnvwohu0503.cloudfront.net lacks integrity attribute
Without SRI, if this CDN is compromised, attackers could inject malicious code.
Got: https://d2kfnvwohu0503.cloudfront.net/css/main.min.css?v=0448d2b3a16473ecb2c6ab8786348384fd9a82779f243cdd4a5bc8c315e1477df0d945c72dcfa36c574fbe565a204ea3b1280c1fa1e1327c02b7da8330182410
Warning::
External link from d2kfnvwohu0503.cloudfront.net lacks integrity attribute
Without SRI, if this CDN is compromised, attackers could inject malicious code.
Got: https://d2kfnvwohu0503.cloudfront.net/css/landing.min.css?v=10f25f976b937ee395e6b38cd972bd6d2a5ea42db27459ef15d5c3d98644b83df4bb398e30af02569d34c959c616ac2ff17767b3cf19e6fa0c542d9a410fd470
Warning::
External script from www.google.com lacks integrity attribute
Without SRI, if this CDN is compromised, attackers could inject malicious code.
Got: https://www.google.com/recaptcha/enterprise.js
Warning::
External script from d2kfnvwohu0503.cloudfront.net lacks integrity attribute
Without SRI, if this CDN is compromised, attackers could inject malicious code.
Got: https://d2kfnvwohu0503.cloudfront.net/js/jstz-1.0.4.min.js?v=ff08a13ff22ac21dc4474115a8e084194fc503f8bb9275eefdbd054f0f2fbf86d3a79a83646f4b4c17d56b81755fa7749b5f9ca5770f6efe45f9cdb767479b55
Warning::
External script from d2kfnvwohu0503.cloudfront.net lacks integrity attribute
Without SRI, if this CDN is compromised, attackers could inject malicious code.
Got: https://d2kfnvwohu0503.cloudfront.net/js/landing.min.js?v=f6bbaa85bda0e2a6ab47a3609523561d2d19d2042b93f15e7d97d65f272799989fabae6f762550c0c947d35d52f5b790926a9cc3437cda6ee59fc090dd06b66e
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=G-YY0306L5MG
SRI Coverage 1 / 10 of external resources have integrity hashes
TagDomainIntegrity
<script>www.gstatic.com✓ Protected
<script>use.typekit.net✗ Missing
<script>d2kfnvwohu0503.cloudfront.net✗ Missing
<script>d2kfnvwohu0503.cloudfront.net✗ Missing
<link>d2kfnvwohu0503.cloudfront.net✗ Missing
<link>d2kfnvwohu0503.cloudfront.net✗ Missing
<script>www.google.com✗ Missing
<script>d2kfnvwohu0503.cloudfront.net✗ Missing
<script>d2kfnvwohu0503.cloudfront.net✗ Missing
<script>www.googletagmanager.com✗ Missing
D
Email Security
Action
DMARC: none
FIX
DMARC: none
Warning::
DMARC policy is none — monitoring only
This only monitors, it doesn't block spoofed emails. Change to p=quarantine or p=reject.
DMARC
Policy none — monitoring only, does not block spoofing Record v=DMARC1;p=none;rua=mailto:dmarc@team.instapaper.com

This only monitors, it doesn't block spoofed emails. Change to p=quarantine or p=reject.

Why this matters

DMARC p=none collects reports but doesn't actually block spoofed mail — phishing emails still reach inboxes.

Learn more ▾

DMARC's three policies are p=none (monitor only), p=quarantine (mark as spam), and p=reject (bounce). Most domains start at p=none to gather data, but stay there forever, leaving spoofers unblocked. After 30 days of clean DMARC reports, graduate to p=quarantine, then p=reject.

Source: DMARC.org / NIST

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

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
C
Known vulnerability matches
Action
6 known vulnerability match(es) against detected tech
REVIEW

Known Vulnerabilities

LibraryVersionSeveritySummaryFixed In
jQuery1.11.0medium3rd party CORS request may execute1.12.0
jQuery1.11.0mediumparseHTML() executes scripts in event handlers2.2.0
jQuery1.11.0lowjQuery 1.x and 2.x are End-of-Life and no longer receiving security updates2.999.999
jQuery1.11.0mediumjQuery before 3.4.0, as used in Drupal, Backdrop CMS, and other products, mishandles jQuery.extend(true, {}, ...) because of Object.prototype pollution3.4.0
jQuery1.11.0mediumpassing HTML containing <option> elements from untrusted sources - even after sanitizing it - to one of jQuery's DOM manipulation methods (i.e. .html(), .append(), and others) may execute untrusted code.3.5.0
jQuery1.11.0mediumRegex in its jQuery.htmlPrefilter sometimes may introduce XSS3.5.0
A+
TLS & Certificates
TLS 1.2, 7 checks passed
PASS
TLS 1.2, 7 checks passed
Info::
TLS 1.2 is used
Got: TLS 1.2
Info::
TLS 1.3 is not negotiated
TLS 1.3 offers improved performance and security. Consider enabling it.
Got: TLS 1.2
Info::
Strong cipher suite is used
Got: TLS_ECDHE_RSA_WITH_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 274 days)
Got: 2027-01-20T23:59:59Z
Info::
Certificate chain has 3 certificates
Info::
Certificate uses modern signature algorithm
Got: SHA256-RSA
Info::
Certificate covers 2 domain(s)
Got: instapaper.com, *.instapaper.com
Info::
Certificate is issued by a trusted CA
Got: CN=Amazon RSA 2048 M04,O=Amazon,C=US

TLS 1.3 offers improved performance and security. Consider enabling it.

Why this matters

TLS 1.3 not in use — connection falls back to 1.2 and pays the extra round-trip.

Learn more ▾

Most clients prefer TLS 1.3 if both sides support it. If your server has TLS 1.3 enabled but it's not being negotiated, check for a downgrade-attack mitigation issue or a misconfigured cipher list. nginx ≥ 1.13.0 and OpenSSL ≥ 1.1.1 support TLS 1.3.

Source: RFC 8446 / Mozilla SSL Config

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 1.2
Cipher Suite
TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256
HTTP Version
HTTP/1.1

Certificate Chain

Leaf Certificate
Subject CN=instapaper.comIssuer CN=Amazon RSA 2048 M04,O=Amazon,C=USValid 2025-12-22T00:00:00Z → 2027-01-20T23:59:59ZExpires in 274 days SANs instapaper.com, *.instapaper.comSignature SHA256-RSASerial cabdc94c1f00595d8a275755de2e4e5
Intermediate (CA Certificate)
Subject CN=Amazon RSA 2048 M04,O=Amazon,C=USIssuer CN=Amazon Root CA 1,O=Amazon,C=USValid 2022-08-23T22:26:35Z → 2030-08-23T22:26:35ZExpires in 1585 days Signature SHA256-RSASerial 773124f2a952e3ed18a58bdb85d1bc0ce5f27
Intermediate (CA Certificate)
Subject CN=Amazon Root CA 1,O=Amazon,C=USIssuer CN=Starfield Services Root Certificate Authority - G2,O=Starfield Technologies\, Inc.,L=Scottsdale,ST=Arizona,C=USValid 2015-05-25T12:00:00Z → 2037-12-31T01:00:00ZExpires in 4271 days Signature SHA256-RSASerial 67f944a2a27cdf3fac2ae2b01f908eeb9c4c6
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) 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.
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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