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Security

· 32 checks — HTTP headers, CSP, TLS handshake, and cookie hygiene rolled into one auditable list.
SCORE
85
GRADE
B
FIX
4
REVIEW
7
PASS
21
INFO
0
Checks
32
21 PASS 7 REVIEW 4 FIX
D
Security Headers
Action
5 of 10 headers properly configured
FIX
5 of 10 headers properly configured
Info::
Strict-Transport-Security is properly configured
Got: max-age=31536000; includeSubdomains; preload
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=()
Critical::
Content-Security-Policy header is missing
CSP is the most important header for preventing XSS attacks. See the CSP section for detailed analysis.
Expected: default-src 'self'
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: snooserv
Info::
Domain is in the Chrome HSTS preload list (status: preloaded)
Got: preloaded

CSP is the most important header for preventing XSS attacks. See the CSP section for detailed analysis.

Expected: default-src 'self'
Why this matters

Without a CSP, a single XSS bug can exfiltrate everything your users type — including credentials.

Learn more ▾

Content-Security-Policy is the browser-enforced firewall against XSS. With a strict CSP, a script injection that would otherwise steal session cookies or rewrite the page is silently blocked. Without it, your only defense is hoping every input on every form is escaped correctly forever.

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
No enforcing CSP policy found
FIX
No enforcing CSP policy found
Critical::
No Content-Security-Policy header found
CSP is the most effective defense against XSS attacks. Add a Content-Security-Policy header to restrict resource loading.
Expected: default-src 'self'

CSP is the most effective defense against XSS attacks. Add a Content-Security-Policy header to restrict resource loading.

Expected: default-src 'self'
Why this matters

Without a CSP, a single XSS bug can exfiltrate everything users type — credentials, payment data, session tokens.

Learn more ▾

Content-Security-Policy is the browser-enforced firewall against XSS. With a strict CSP, a script injection that would otherwise steal session cookies is silently blocked. Without it, your only defense is hoping every input on every form is escaped correctly forever. Start in Report-Only mode, fix violations, then graduate to enforcing.

Source: OWASP / MDN

D
Cross-Origin Tab Safety
Action
5 of 5 new-tab link(s) missing rel=noopener
FIX
5 of 5 new-tab link(s) missing rel=noopener
Warning::
5 link(s) open in a new tab without rel=noopener
Without rel="noopener", the destination tab can navigate the original tab via window.opener -- a reverse-tabnabbing phishing primitive. Modern browsers default to noopener since Chrome 88 / Firefox 79 / Safari 12.1, but explicit rel="noopener noreferrer" remains the documented best practice for older browsers, in-app webviews, and security scanners.
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
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.
B
CSP Inline-Style Readiness
3 inline style attribute(s) detected
REVIEW
3 inline style attribute(s) detected
Info::
3 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. 3 inline style(s) is low. Affected element types include: div, textarea, iframe. 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
Subresource Integrity Adoption
50% SRI adoption (1/2 third-party resources)
REVIEW
50% SRI adoption (1/2 third-party resources)
Info::
SRI adoption: 1/2 third-party resources protected (50%)
Of 2 third-party `<script>` / `<link rel=stylesheet>` resources, 1 (50%) 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 1 examples): - https://www.google.com/recaptcha/api.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: 50% (1/2)
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
Referrer-Policy Strictness
Referrer-Policy header not set -- browser default applies (modern: strict-origin-when-cross-origin; legacy browsers: no-referrer-when-downgrade)
REVIEW
Referrer-Policy header not set -- browser default applies (modern: strict-origin-when-cross-origin; legacy browsers: no-referrer-when-downgrade)
Info::
Referrer-Policy header not set -- browser default applies
Without an explicit `Referrer-Policy` header, the browser falls back to its default policy. Modern browsers (Chrome 85+, Firefox 87+, Safari 15+) default to `strict-origin-when-cross-origin`, which is privacy-safe. Legacy browsers default to the leaky `no-referrer-when-downgrade`, which sends the full URL (including path + query) on cross-origin HTTPS-to-HTTPS requests. Set an explicit header to ensure consistent behavior: ``` Referrer-Policy: strict-origin-when-cross-origin ``` This matches the modern browser default and is privacy-safe without breaking referrer-based same-origin analytics.
Got: header absent
C
Subresource Integrity
Action
1 of 2 external resources have SRI
REVIEW
1 of 2 external resources have SRI
Info::
script from www.gstatic.com has SRI protection
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/api.js
SRI Coverage 1 / 2 of external resources have integrity hashes
TagDomainIntegrity
<script>www.gstatic.com✓ Protected
<script>www.google.com✗ Missing
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, 8 checks passed
PASS
TLS 1.3, 8 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 enabled
Info::
Certificate is valid (expires in 147 days)
Got: 2026-10-04T23:59:59Z
Info::
Certificate chain has 2 certificates
Info::
Certificate uses modern signature algorithm
Got: SHA256-RSA
Info::
Certificate covers 2 domain(s)
Got: *.reddit.com, reddit.com
Info::
Certificate is issued by a trusted CA
Got: CN=DigiCert Global G2 TLS RSA SHA256 2020 CA1,O=DigiCert Inc,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=*.reddit.com,O=Reddit\, Inc.,L=San Francisco,ST=California,C=USIssuer CN=DigiCert Global G2 TLS RSA SHA256 2020 CA1,O=DigiCert Inc,C=USValid 2026-04-08T00:00:00Z → 2026-10-04T23:59:59ZExpires in 147 days SANs *.reddit.com, reddit.comSignature SHA256-RSASerial e9e4f5d82fcc4145fd88fd39c2a3111
Intermediate (CA Certificate)
Subject CN=DigiCert Global G2 TLS RSA SHA256 2020 CA1,O=DigiCert Inc,C=USIssuer CN=DigiCert Global Root G2,OU=www.digicert.com,O=DigiCert Inc,C=USValid 2021-03-30T00:00:00Z → 2031-03-29T23:59:59ZExpires in 1784 days Signature SHA256-RSASerial cf5bd062b5602f47ab8502c23ccf066
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+
security.txt
Vulnerability disclosure policy
PASS
Vulnerability disclosure policy
Info::
security.txt found
Got: https://reddit.com/.well-known/security.txt
Info::
security.txt is PGP signed

security.txt

Contact: mailto:whitehats@reddit.com
Expires: 2027-01-05T23:00:00.000Z
Encryption: https://keys.openpgp.org/vks/v1/by-fingerprint/D5C0F8C4441E3347C857805472DF3589162239CF
Policy: https://www.reddit.com/.well-known/security.txt
A+
Trusted Types (XSS Sink Hardening)
No CSP header -- Trusted Types check is N/A
PASS
No CSP header -- Trusted Types check is N/A
Info::
No CSP header found -- Trusted Types check is N/A
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
HTTP status is non-2xx -- soft-404 check is N/A
PASS
HTTP status is non-2xx -- soft-404 check is N/A
Info::
HTTP status is non-2xx -- soft-404 check is N/A
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+
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+
Source Map Exposure
Source-map probe didn't run on this scan
PASS
Source-map probe didn't run on this scan
Info::
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
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+
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
/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, DKIM, BIMI
PASS
DMARC: reject, SPF: ~all, DKIM, BIMI
Info::
DMARC policy is reject — strongest protection
Info::
SPF ends in ~all (soft fail)
Soft fail tells receivers to accept-but-mark unauthorized mail. Migrate to -all once you've confirmed all legitimate senders are listed (DMARC aggregate reports help verify).
Info::
DKIM configured (selectors: google, k1)
Info::
MTA-STS not configured
MTA-STS forces inbound mail to use TLS, preventing downgrade attacks. Requires both a TXT record at _mta-sts.<domain> and a policy file at https://mta-sts.<domain>/.well-known/mta-sts.txt.
Info::
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>.
Info::
BIMI configured and DMARC enforced — logo will display
DMARC
Policy reject — strongest protection Record v=DMARC1; p=reject; fo=1; ruf=mailto:reddit@us.cp-dmarc.com; rua=mailto:reddit@us.cp-dmarc.com

Soft fail tells receivers to accept-but-mark unauthorized mail. Migrate to -all once you've confirmed all legitimate senders are listed (DMARC aggregate reports help verify).

Why this matters

Informational: a labeled value pair from the audit.

MTA-STS forces inbound mail to use TLS, preventing downgrade attacks. Requires both a TXT record at _mta-sts.<domain> and a policy file at https://mta-sts.<domain>/.well-known/mta-sts.txt.

Why this matters

Without MTA-STS, inbound mail can be silently downgraded to plain SMTP by a network attacker.

Learn more ▾

MTA-STS (RFC 8461) tells sending mail servers to use TLS and to refuse delivery if TLS fails. Requires both a TXT record at _mta-sts.<domain> AND a policy file at https://mta-sts.<domain>/.well-known/mta-sts.txt. Without it, an active attacker on the network path can strip STARTTLS and read the email in plaintext.

Source: RFC 8461

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

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) 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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