Security - https://math-kit.pages.dev BeaverCheck Audit

F

Subresource Integrity Adoption

Action

0% SRI adoption (0/2 third-party resources)

FIX

0% SRI adoption (0/2 third-party resources)

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://www.googletagmanager.com/gtag/js?id=G-7CVV9WMFET - https://static.cloudflareinsights.com/beacon.min.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

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-7CVV9WMFET

External script from static.cloudflareinsights.com lacks integrity attribute

Without SRI, if this CDN is compromised, attackers could inject malicious code.

Got: https://static.cloudflareinsights.com/beacon.min.js

SRI Coverage 0 / 2 of external resources have integrity hashes

Tag	Domain	Integrity
<script>	www.googletagmanager.com	✗ Missing
<script>	static.cloudflareinsights.com	✗ Missing

F

Email Security

Action

no DMARC, no SPF

FIX

no DMARC, no SPF

No DMARC record found

Without DMARC, email receivers have no policy for handling authentication failures. Add a TXT record at _dmarc.<domain> starting with v=DMARC1.

No SPF record found

Without SPF (Sender Policy Framework), receivers can't tell which servers are authorized to send mail for your domain. Add a TXT record at the apex starting with v=spf1, ending in -all.

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.

MTA-STS policy file present but DNS record missing

The policy file exists but no _mta-sts TXT record was found. Senders rely on the TXT record to discover and version the policy.

TLS-RPT not configured

TLS-RPT (RFC 8460) lets MTAs report TLS-handshake failures, so you can detect and fix MTA-STS misconfigurations. Add a TXT record at _smtp._tls.<domain>.

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

No DMARC record found

Without DMARC, email receivers have no policy for handling authentication failures from your domain.

Without DMARC, email receivers have no policy for handling authentication failures. Add a TXT record at _dmarc.<domain> starting with v=DMARC1.

Why this matters

Without DMARC, anyone can send phishing emails using your domain name.

Learn more ▾

DMARC tells receiving mail servers what to do with email that fails SPF/DKIM checks for your domain. With a strict 'p=reject' policy, spoofed emails get bounced; without it they reach the inbox. Domains used in phishing campaigns lose deliverability and brand trust fast.

Source: DMARC.org / NIST

Without SPF (Sender Policy Framework), receivers can't tell which servers are authorized to send mail for your domain. Add a TXT record at the apex starting with v=spf1, ending in -all.

Why this matters

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

The policy file exists but no _mta-sts TXT record was found. Senders rely on the TXT record to discover and version the policy.

Why this matters

MTA-STS policy file is reachable but no _mta-sts TXT record exists, so senders can't discover or version-pin the policy.

Learn more ▾

Senders look up the _mta-sts TXT record first to learn the current policy ID; without it they treat the policy as absent. Publish a TXT record at _mta-sts.<domain> with v=STSv1; id=<policy-version>.

Source: RFC 8461 §3.1

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

TLS-RPT (RFC 8460) lets MTAs report TLS-handshake failures, so you can detect and fix MTA-STS misconfigurations. Add a TXT record at _smtp._tls.<domain>.

Why this matters

Without TLS-RPT, you have no visibility into inbound TLS failures — MTA-STS misconfigurations stay hidden until users complain.

Learn more ▾

TLS-RPT (RFC 8460) is the feedback channel for MTA-STS: senders post aggregate reports of TLS-handshake failures to the URI in your _smtp._tls TXT record. Without it, an MTA-STS misconfiguration silently rejects mail and you find out only when someone notices missing email.

Source: RFC 8460

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.

B

Content Security Policy

2 of 11 CSP checks passed

REVIEW

2 of 11 CSP checks passed

Raw CSP policy

Got: frame-ancestors 'none'

default-src directive is missing

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

Expected: default-src 'self'

No script-src or default-src to check for 'unsafe-inline'

No script-src or default-src to check for 'unsafe-eval'

No script-src or default-src to check for wildcard

object-src falls back to default-src

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'

frame-ancestors directive is set

Got: frame-ancestors 'none'

form-action directive is missing

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

Expected: form-action 'self'

upgrade-insecure-requests is not set

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

Expected: upgrade-insecure-requests

Content-Security-Policy-Report-Only is also set

A report-only policy is active alongside the enforcing policy for monitoring.

Got: default-src 'self'; script-src 'self' 'unsafe-inline' https://www.googletagmanager.com https://static.cloudflareinsights…

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.

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

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

A report-only policy is active alongside the enforcing policy for monitoring.

Why this matters

Running enforcing + Report-Only in parallel lets you test stricter directives safely before promoting them.

Source: MDN CSP

Parsed Policy

frame-ancestors 'none'

C

security.txt

Action

No security.txt file found

REVIEW

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

CSP Inline-Style Readiness

1 inline style attribute(s) detected

REVIEW

1 inline style attribute(s) detected

Each `style=""` attribute forces `style-src 'unsafe-inline'` in any Content-Security-Policy, which negates most of CSP's XSS-mitigation value. 1 inline style(s) is low. Affected element types include: div. Move styles to a stylesheet; use CSS custom properties for runtime-dynamic values; or adopt a nonce/hash CSP policy. Most teams take the stylesheet path because it's also a maintainability win.

B

Trusted Types (XSS Sink Hardening)

Trusted Types not enabled

REVIEW

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

CORS Configuration

Action

Origin: *

REVIEW

Origin: *

Access-Control-Allow-Origin: * — unrestricted

Any website can read this resource's response. Appropriate for public APIs but not for user-specific content.

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.

Header	Value	Status
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

Security Headers

8 of 10 headers properly configured

PASS

8 of 10 headers properly configured

HSTS is enabled

Got: max-age=31536000; includeSubDomains

X-Content-Type-Options is properly configured

Got: nosniff

X-Frame-Options is properly configured

Got: DENY

Referrer-Policy is properly configured

Got: strict-origin-when-cross-origin

Permissions-Policy is set

Got: camera=(), microphone=(), geolocation=(), payment=(), usb=(), accelerometer=(), gyroscope=(), magnetometer=(), idle-detection=(), interest-cohort=()

Content-Security-Policy is present

Got: frame-ancestors 'none'

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

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

X-Powered-By header is not present

Server header is present without version info

Got: cloudflare

Domain is in the Chrome HSTS preload list (status: preloaded)

Got: preloaded

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

A+

TLS & Certificates

TLS 1.3, 8 checks passed

PASS

TLS 1.3, 8 checks passed

TLS 1.3 is used

Got: TLS 1.3

Strong cipher suite is used

Got: TLS_AES_128_GCM_SHA256

HTTP/2 is negotiated

Got: h2

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.

Certificate is valid (expires in 71 days)

Got: 2027-01-09T14:29:59Z

Certificate chain has 4 certificates

Certificate uses modern signature algorithm

Got: ECDSA-SHA384

Certificate covers 2 domain(s)

Got: *.math-kit.pages.dev, math-kit.pages.dev

Certificate is issued by a trusted CA

Got: CN=YE2,O=Let's Encrypt,C=US

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

h2 (HTTP/2)

Certificate Chain

Leaf Certificate

Subject CN=math-kit.pages.devIssuer CN=YE2,O=Let's Encrypt,C=USValid 2026-10-11T14:30:00Z → 2027-01-09T14:29:59ZExpires in 71 days SANs *.math-kit.pages.dev, math-kit.pages.devSignature ECDSA-SHA384Serial 66d25cbe3a9826c9e0ddef72ce3b59df269

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 674 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 2135 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 2135 days Signature SHA256-RSASerial 6c8f1dc727c7117f7baf853ac980f9cd

A+

Cookie Security

No cookies set — no cookie security risks

PASS

No cookies set — no cookie security risks

No cookies detected — no cookie security risks to report.

A+

Cookie Hygiene

No cookies set -- cookie-hygiene check is N/A

PASS

No cookies set -- cookie-hygiene check is N/A

No cookies set

A

WAF / Bot Protection

Cloudflare

PASS

Cloudflare

Cloudflare detected

Detected via: cf-ray: a52433fc1f262143-CDG

Got: Cloudflare

A+

Cross-Origin Tab Safety

All 3 new-tab link(s) carry rel=noopener

PASS

All 3 new-tab link(s) carry rel=noopener

A+

Bot Challenge Detection

Scan reached real page content (no bot-protection interstitial)

PASS

Scan reached real page content (no bot-protection interstitial)

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

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

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

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

No maintenance-mode signals detected

A

CORS Depth

1 CORS depth signal(s) detected

PASS

1 CORS depth signal(s) detected

CORS allows any origin (`Access-Control-Allow-Origin: *`)

Any website can fetch this URL via JavaScript and read the response body. Acceptable for genuinely public APIs (e.g. CDN-served static assets). Risky if the URL returns user-specific or session-derived data, since other origins can scrape it via the user's browser without needing credentials. Narrow Allow-Origin to a specific origin allow-list when the response is sensitive.

Got: Allow-Origin: *

A

Permissions-Policy Granularity

80% high-risk feature coverage (8/10)

PASS

80% high-risk feature coverage (8/10)

Permissions-Policy covers 8/10 high-risk features (80%)

The Permissions-Policy header explicitly declares policies for 8/10 high-risk features. Covered: camera, microphone, geolocation, payment, usb, accelerometer, gyroscope, magnetometer Not declared (default-allow): serial, midi The non-declared features fall back to their spec-default policy (usually `self`), which means an XSS-injected or compromised iframe could request them. For features the page genuinely doesn't use, declare `feature=()` to fully close them.

Got: 80% (8/10)

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)

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

Source-map probe didn't run on this scan

PASS

Source-map probe didn't run on this scan

A+

HTML Version Disclosure

No software-version disclosures in HTML

PASS

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

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

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

A+

JS Library Vulnerabilities

No known vulnerabilities

PASS

No known vulnerabilities

No known JavaScript library vulnerabilities detected

No known JavaScript library vulnerabilities detected.

A+

Information Leakage

No exposures

PASS

No exposures

No security.txt found

Consider adding a security.txt at /.well-known/security.txt.

No sensitive files exposed

No sensitive files exposed — all paths returned 404.

Path	Status	Category	Risk
/.git/HEAD	✓ Not found	Version Control	—
/.git/config	✓ Not found	Version Control	—
/.svn/entries	✓ Not found	Version Control	—
/.env	✓ Not found	Configuration	—
/.env.local	✓ Not found	Configuration	—
/.env.production	✓ Not found	Configuration	—
/wp-config.php	✓ Not found	Configuration	—
/.htaccess	✓ Not found	Configuration	—
/phpinfo.php	✓ Not found	Debug	—
/server-status	✓ Not found	Debug	—
/server-info	✓ Not found	Debug	—
/.well-known/security.txt	✓ Not found	Security Policy	—
/package.json	✓ Not found	dependency-manifest	—
/composer.json	✓ Not found	dependency-manifest	—
/Gemfile	✓ Not found	dependency-manifest	—
/Gemfile.lock	✓ Not found	dependency-manifest	—
/requirements.txt	✓ Not found	dependency-manifest	—
/pom.xml	✓ Not found	dependency-manifest	—
/.gitlab-ci.yml	✓ Not found	ci-config	—
/.travis.yml	✓ Not found	ci-config	—

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))

No API specs or GraphQL introspection found (probed 11 path(s))

A+

Permissions-Policy

10 directives, 0 missing

PASS

10 directives, 0 missing

camera=() — blocked for all origins

microphone=() — blocked for all origins

geolocation=() — blocked for all origins

payment=() — blocked for all origins

usb=() — blocked for all origins

accelerometer=() — blocked for all origins

gyroscope=() — blocked for all origins

magnetometer=() — blocked for all origins

idle-detection=() — blocked for all origins

interest-cohort=() — blocked for all origins

Raw Header

camera=() microphone=() geolocation=() payment=() usb=() accelerometer=() gyroscope=() magnetometer=() idle-detection=() interest-cohort=()

Feature Permissions

Blocked Self Only Unrestricted Not Set

camera Blocked

microphone Blocked

geolocation Blocked

payment Blocked

usb Blocked

accelerometer Blocked

gyroscope Blocked

magnetometer Blocked

idle-detection Blocked

interest-cohort Blocked

A+

Transport Security

HTTP/3, HSTS, and TLS version analysis

PASS

HTTP/3, HSTS, and TLS version analysis

HTTP/3 (QUIC) supported

The server advertises HTTP/3 via Alt-Svc for faster connections on mobile networks.

HSTS enabled (includeSubDomains)

TLS 1.3 in use (fastest handshake, 1-RTT)