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Security

· 12 checks — HTTP headers, CSP, TLS handshake, and cookie hygiene rolled into one auditable list.
SCORE
66
GRADE
D
FIX
4
REVIEW
4
PASS
4
INFO
0
Checks
12
4 PASS 4 REVIEW 4 FIX
D
Cookie Security
Action
6 cookies analyzed, 6 checks passed
FIX
6 cookies analyzed, 6 checks passed
Info::
Cookie 'grauth' has the Secure flag
Info::
Cookie 'grauth' has the HttpOnly flag
Info::
Cookie 'grauth' has SameSite=None
Info::
Cookie 'csrf-token' has the Secure flag
Warning::
Cookie 'csrf-token' is missing the HttpOnly flag
Without HttpOnly, this cookie can be accessed by JavaScript, making it vulnerable to XSS-based theft.
Info::
Cookie 'csrf-token' has SameSite=None
Critical::
Cookie 'gnar_containerId' is missing the Secure flag
Without the Secure flag, this cookie can be sent over unencrypted HTTP, exposing it to interception.
Warning::
Cookie 'gnar_containerId' is missing the HttpOnly flag
Without HttpOnly, this cookie can be accessed by JavaScript, making it vulnerable to XSS-based theft.
Warning::
Cookie 'gnar_containerId' has no SameSite attribute
Without an explicit SameSite attribute, browser default behavior varies. Set SameSite=Lax or Strict.
Critical::
Cookie 'gnar_websiteSessionId' is missing the Secure flag
Without the Secure flag, this cookie can be sent over unencrypted HTTP, exposing it to interception.
Warning::
Cookie 'gnar_websiteSessionId' is missing the HttpOnly flag
Without HttpOnly, this cookie can be accessed by JavaScript, making it vulnerable to XSS-based theft.
Warning::
Cookie 'gnar_websiteSessionId' has no SameSite attribute
Without an explicit SameSite attribute, browser default behavior varies. Set SameSite=Lax or Strict.
Critical::
Cookie 'browser_info' is missing the Secure flag
Without the Secure flag, this cookie can be sent over unencrypted HTTP, exposing it to interception.
Warning::
Cookie 'browser_info' is missing the HttpOnly flag
Without HttpOnly, this cookie can be accessed by JavaScript, making it vulnerable to XSS-based theft.
Warning::
Cookie 'browser_info' has no SameSite attribute
Without an explicit SameSite attribute, browser default behavior varies. Set SameSite=Lax or Strict.
Info::
Cookie 'currentLocale' has the Secure flag
Warning::
Cookie 'currentLocale' is missing the HttpOnly flag
Without HttpOnly, this cookie can be accessed by JavaScript, making it vulnerable to XSS-based theft.
Warning::
Cookie 'currentLocale' has no SameSite attribute
Without an explicit SameSite attribute, browser default behavior varies. Set SameSite=Lax or Strict.
6 cookies analyzed 3 critical 9 warnings
NameSecureHttpOnlySameSiteSizeIssues
grauth✓✓None86 B—
csrf-token✓✗None48 B1
gnar_containerId✗✗—32 B3
gnar_websiteSessionId✗✗—57 B3
browser_info✗✗—68 B3
currentLocale✓✗—18 B2
F
Subresource Integrity
Action
0 of 50 external resources have SRI
FIX
0 of 50 external resources have SRI
Warning::
External script from scripts.clarity.ms lacks integrity attribute
Without SRI, if this CDN is compromised, attackers could inject malicious code.
Got: https://scripts.clarity.ms/0.8.59/clarity.js
Warning::
External script from analytics.tiktok.com lacks integrity attribute
Without SRI, if this CDN is compromised, attackers could inject malicious code.
Got: https://analytics.tiktok.com/i18n/pixel/static/identify_5cff1caf.js
Warning::
External script from www.clarity.ms lacks integrity attribute
Without SRI, if this CDN is compromised, attackers could inject malicious code.
Got: https://www.clarity.ms/tag/uet/4001981?insights=1
Warning::
External script from analytics.tiktok.com lacks integrity attribute
Without SRI, if this CDN is compromised, attackers could inject malicious code.
Got: https://analytics.tiktok.com/i18n/pixel/static/main.MWE0ZWQ3ZWQwMQ.js
Warning::
External script from j.6sc.co lacks integrity attribute
Without SRI, if this CDN is compromised, attackers could inject malicious code.
Got: https://j.6sc.co/6si.min.js
Warning::
External script from analytics.tiktok.com lacks integrity attribute
Without SRI, if this CDN is compromised, attackers could inject malicious code.
Got: https://analytics.tiktok.com/i18n/pixel/events.js?sdkid=D1E399BC77UB0U4249V0&lib=ttq
Warning::
External script from utt.impactcdn.com lacks integrity attribute
Without SRI, if this CDN is compromised, attackers could inject malicious code.
Got: https://utt.impactcdn.com/A6052161-35a5-43f1-815e-1b952086565a1.js
Warning::
External script from d34r8q7sht0t9k.cloudfront.net lacks integrity attribute
Without SRI, if this CDN is compromised, attackers could inject malicious code.
Got: https://d34r8q7sht0t9k.cloudfront.net/tag.js
Warning::
External script from connect.facebook.net lacks integrity attribute
Without SRI, if this CDN is compromised, attackers could inject malicious code.
Got: https://connect.facebook.net/signals/config/828127113879905?v=2.9.291&r=stable&domain=www.grammarly.com&hme=295b1b33901e14aeab879c0b58f907ef4d5f44fdd19814310771af911c5f6ac8&ex_m=102%2C198%2C147%2C22%2C70%2C71%2C139%2C66%2C65%2C11%2C155%2C88%2C16%2C132%2C124%2C37%2C73%2C76%2C130%2C152%2C157%2C8%2C4%2C5%2C7%2C6%2C3%2C89%2C99%2C158%2C163%2C212%2C60%2C179%2C180%2C53%2C267%2C30%2C72%2C224%2C223%2C222%2C23%2C32%2C101%2C59%2C10%2C61%2C95%2C96%2C97%2C103%2C127%2C31%2C29%2C129%2C126%2C125%2C148%2C74%2C151%2C149%2C150%2C48%2C58%2C120%2C15%2C154%2C43%2C254%2C255%2C253%2C26%2C27%2C28%2C46%2C140%2C75%2C110%2C18%2C20%2C42%2C38%2C40%2C39%2C81%2C90%2C94%2C108%2C138%2C141%2C44%2C109%2C24%2C21%2C116%2C67%2C35%2C143%2C142%2C144%2C135%2C133%2C25%2C34%2C57%2C107%2C153%2C68%2C17%2C145%2C112%2C79%2C64%2C19%2C83%2C84%2C113%2C82%2C33%2C284%2C205%2C194%2C195%2C193%2C287%2C279%2C50%2C206%2C105%2C128%2C78%2C118%2C52%2C45%2C47%2C111%2C117%2C123%2C56%2C62%2C51%2C54%2C98%2C156%2C1%2C121%2C14%2C119%2C12%2C2%2C55%2C91%2C63%2C115%2C87%2C86%2C159%2C160%2C92%2C93%2C9%2C122%2C100%2C49%2C136%2C85%2C77%2C69%2C114%2C104%2C41%2C137%2C0%2C80%2C131%2C134%2C146%2C36%2C106%2C13%2C161
Warning::
External script from connect.facebook.net lacks integrity attribute
Without SRI, if this CDN is compromised, attackers could inject malicious code.
Got: https://connect.facebook.net/en_US/fbevents.js
Warning::
External script from collector-21641.us.tvsquared.com lacks integrity attribute
Without SRI, if this CDN is compromised, attackers could inject malicious code.
Got: https://collector-21641.us.tvsquared.com/tv2track.js
Warning::
External script from cdn.pdst.fm lacks integrity attribute
Without SRI, if this CDN is compromised, attackers could inject malicious code.
Got: https://cdn.pdst.fm/ping.min.js
Warning::
External script from bat.bing.com lacks integrity attribute
Without SRI, if this CDN is compromised, attackers could inject malicious code.
Got: //bat.bing.com/bat.js
Warning::
External script from cdn.taboola.com lacks integrity attribute
Without SRI, if this CDN is compromised, attackers could inject malicious code.
Got: https://cdn.taboola.com/libtrc/unip/1326138/tfa.js
Warning::
External script from snap.licdn.com lacks integrity attribute
Without SRI, if this CDN is compromised, attackers could inject malicious code.
Got: https://snap.licdn.com/li.lms-analytics/insight.min.js
Warning::
External script from a.quora.com lacks integrity attribute
Without SRI, if this CDN is compromised, attackers could inject malicious code.
Got: https://a.quora.com/qevents.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=G-CBK9K2ZWWE&l=dataLayerAt1333&cx=c&gtm=4e6460
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=DC-11910764&l=dataLayerAt1333&cx=c&gtm=4e6460
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=DC-10353179&l=dataLayerAt1333&cx=c&gtm=4e6460
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=DC-10353176&l=dataLayerAt1333&cx=c&gtm=4e6460
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=AW-956476927&l=dataLayerAt1333&cx=c&gtm=4e6460
Warning::
External script from www.google-analytics.com lacks integrity attribute
Without SRI, if this CDN is compromised, attackers could inject malicious code.
Got: https://www.google-analytics.com/plugins/ua/ecommerce.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/gtm.js?id=GTM-NQ3XB9&l=dataLayerAt1333
Warning::
External script from www.google-analytics.com lacks integrity attribute
Without SRI, if this CDN is compromised, attackers could inject malicious code.
Got: //www.google-analytics.com/analytics.js
Warning::
External link from static-web.grammarly.com lacks integrity attribute
Without SRI, if this CDN is compromised, attackers could inject malicious code.
Got: https://static-web.grammarly.com/cms/master/_next/static/css/e9f86793ce73c13a.css
Warning::
External link from static-web.grammarly.com lacks integrity attribute
Without SRI, if this CDN is compromised, attackers could inject malicious code.
Got: https://static-web.grammarly.com/cms/master/_next/static/css/3540ba9e956cf59a.css
Warning::
External link from static-web.grammarly.com lacks integrity attribute
Without SRI, if this CDN is compromised, attackers could inject malicious code.
Got: https://static-web.grammarly.com/cms/master/_next/static/css/7b7e1910fdad8012.css
Warning::
External script from static-web.grammarly.com lacks integrity attribute
Without SRI, if this CDN is compromised, attackers could inject malicious code.
Got: https://static-web.grammarly.com/cms/master/_next/static/chunks/polyfills-42372ed130431b0a.js
Warning::
External script from accounts.google.com lacks integrity attribute
Without SRI, if this CDN is compromised, attackers could inject malicious code.
Got: https://accounts.google.com/gsi/client
Warning::
External script from static-web.grammarly.com lacks integrity attribute
Without SRI, if this CDN is compromised, attackers could inject malicious code.
Got: https://static-web.grammarly.com/web-heartbeat/latest/index.js
Warning::
External script from static-web.grammarly.com lacks integrity attribute
Without SRI, if this CDN is compromised, attackers could inject malicious code.
Got: https://static-web.grammarly.com/cms/master/_next/static/chunks/125.bf0591b6cf20737e.js
Warning::
External script from static-web.grammarly.com lacks integrity attribute
Without SRI, if this CDN is compromised, attackers could inject malicious code.
Got: https://static-web.grammarly.com/cms/master/_next/static/chunks/webpack-78f30d23d4a7498f.js
Warning::
External script from static-web.grammarly.com lacks integrity attribute
Without SRI, if this CDN is compromised, attackers could inject malicious code.
Got: https://static-web.grammarly.com/cms/master/_next/static/chunks/framework-18871a3a7164e80f.js
Warning::
External script from static-web.grammarly.com lacks integrity attribute
Without SRI, if this CDN is compromised, attackers could inject malicious code.
Got: https://static-web.grammarly.com/cms/master/_next/static/chunks/main-a1ca2a318bff5472.js
Warning::
External script from static-web.grammarly.com lacks integrity attribute
Without SRI, if this CDN is compromised, attackers could inject malicious code.
Got: https://static-web.grammarly.com/cms/master/_next/static/chunks/pages/_app-42ab6431f4f86533.js
Warning::
External script from static-web.grammarly.com lacks integrity attribute
Without SRI, if this CDN is compromised, attackers could inject malicious code.
Got: https://static-web.grammarly.com/cms/master/_next/static/chunks/2665999f-54d41965add03933.js
Warning::
External script from static-web.grammarly.com lacks integrity attribute
Without SRI, if this CDN is compromised, attackers could inject malicious code.
Got: https://static-web.grammarly.com/cms/master/_next/static/chunks/1a192442-e4e5b1da91b22ec4.js
Warning::
External script from static-web.grammarly.com lacks integrity attribute
Without SRI, if this CDN is compromised, attackers could inject malicious code.
Got: https://static-web.grammarly.com/cms/master/_next/static/chunks/345-b3c0ea41a809d894.js
Warning::
External script from static-web.grammarly.com lacks integrity attribute
Without SRI, if this CDN is compromised, attackers could inject malicious code.
Got: https://static-web.grammarly.com/cms/master/_next/static/chunks/151-c24adecc0ed805dc.js
Warning::
External script from static-web.grammarly.com lacks integrity attribute
Without SRI, if this CDN is compromised, attackers could inject malicious code.
Got: https://static-web.grammarly.com/cms/master/_next/static/chunks/pages/render-b5a9ba44889e5a7a.js
Warning::
External script from static-web.grammarly.com lacks integrity attribute
Without SRI, if this CDN is compromised, attackers could inject malicious code.
Got: https://static-web.grammarly.com/cms/master/_next/static/SB-nAS9CKUdTc-aHaf6kE/_buildManifest.js
Warning::
External script from static-web.grammarly.com lacks integrity attribute
Without SRI, if this CDN is compromised, attackers could inject malicious code.
Got: https://static-web.grammarly.com/cms/master/_next/static/SB-nAS9CKUdTc-aHaf6kE/_ssgManifest.js
Warning::
External script from googleads.g.doubleclick.net lacks integrity attribute
Without SRI, if this CDN is compromised, attackers could inject malicious code.
Got: https://googleads.g.doubleclick.net/pagead/viewthroughconversion/956476927/?random=1775594523903&cv=11&fst=1775594523903&bg=ffffff&guid=ON&async=1&en=gtag.config&gtm=45be6460v9101027542z871625002za20gzb71625002zd71625002xec&gcd=13t3t3t3t5l1&dma=0&tag_exp=0~115616985~115938466~115938468~116701382~116991817~117884344~118392705&u_w=800&u_h=600&url=https%3A%2F%2Fwww.grammarly.com%2F&frm=0&tiba=Grammarly%3A%20Free%20AI%20Writing%20Assistance&hn=www.googleadservices.com&npa=0&pscdl=noapi&auid=726084373.1775594524&uaa=x86&uab=64&uafvl=Not-A.Brand%3B24.0.0.0%7CChromium%3B146.0.7680.164&uamb=0&uam=&uap=Linux&uapv=&uaw=0&data=event%3Dgtag.config&rfmt=3&fmt=4
Warning::
External script from googleads.g.doubleclick.net lacks integrity attribute
Without SRI, if this CDN is compromised, attackers could inject malicious code.
Got: https://googleads.g.doubleclick.net/pagead/viewthroughconversion/956476927/?random=1775594523995&cv=11&fst=1775594523995&bg=ffffff&guid=ON&async=1&gtm=45be6460v9101027542z871625002za20gzb71625002zd71625002xea&gcd=13t3t3t3t5l1&dma=0&tag_exp=0~115616985~115938466~115938468~116701382~116991817~117884344~118392705&u_w=800&u_h=600&url=https%3A%2F%2Fwww.grammarly.com%2F&frm=0&tiba=Grammarly%3A%20Free%20AI%20Writing%20Assistance&hn=www.googleadservices.com&npa=0&pscdl=noapi&auid=726084373.1775594524&uaa=x86&uab=64&uafvl=Not-A.Brand%3B24.0.0.0%7CChromium%3B146.0.7680.164&uamb=0&uam=&uap=Linux&uapv=&uaw=0&_tu=CA&rfmt=3&fmt=4
Warning::
External script from bat.bing.com lacks integrity attribute
Without SRI, if this CDN is compromised, attackers could inject malicious code.
Got: https://bat.bing.com/p/action/4001981.js
Warning::
External link from accounts.google.com lacks integrity attribute
Without SRI, if this CDN is compromised, attackers could inject malicious code.
Got: https://accounts.google.com/gsi/style
Warning::
External script from transcend-cdn.com lacks integrity attribute
Without SRI, if this CDN is compromised, attackers could inject malicious code.
Got: https://transcend-cdn.com/cm/1c1f8e90-47d0-4bba-a1a2-472d59b002a2/airgap.js
Warning::
External script from j.6sc.co lacks integrity attribute
Without SRI, if this CDN is compromised, attackers could inject malicious code.
Got: https://j.6sc.co/j/6a904767-a8ac-4a46-83bf-aacb747de3f0.js
Warning::
External script from js.adsrvr.org lacks integrity attribute
Without SRI, if this CDN is compromised, attackers could inject malicious code.
Got: https://js.adsrvr.org/up_loader.1.1.0.js
Warning::
External script from js.zi-scripts.com lacks integrity attribute
Without SRI, if this CDN is compromised, attackers could inject malicious code.
Got: https://js.zi-scripts.com/zi-tag.js
SRI Coverage 0 / 50 of external resources have integrity hashes
TagDomainIntegrity
<script>scripts.clarity.ms✗ Missing
<script>analytics.tiktok.com✗ Missing
<script>www.clarity.ms✗ Missing
<script>analytics.tiktok.com✗ Missing
<script>j.6sc.co✗ Missing
<script>analytics.tiktok.com✗ Missing
<script>utt.impactcdn.com✗ Missing
<script>d34r8q7sht0t9k.cloudfront.net✗ Missing
<script>connect.facebook.net✗ Missing
<script>connect.facebook.net✗ Missing
<script>collector-21641.us.tvsquared.com✗ Missing
<script>cdn.pdst.fm✗ Missing
<script>bat.bing.com✗ Missing
<script>cdn.taboola.com✗ Missing
<script>snap.licdn.com✗ Missing
<script>a.quora.com✗ Missing
<script>www.googletagmanager.com✗ Missing
<script>www.googletagmanager.com✗ Missing
<script>www.googletagmanager.com✗ Missing
<script>www.googletagmanager.com✗ Missing
<script>www.googletagmanager.com✗ Missing
<script>www.google-analytics.com✗ Missing
<script>www.googletagmanager.com✗ Missing
<script>www.google-analytics.com✗ Missing
<link>static-web.grammarly.com✗ Missing
<link>static-web.grammarly.com✗ Missing
<link>static-web.grammarly.com✗ Missing
<script>static-web.grammarly.com✗ Missing
<script>accounts.google.com✗ Missing
<script>static-web.grammarly.com✗ Missing
<script>static-web.grammarly.com✗ Missing
<script>static-web.grammarly.com✗ Missing
<script>static-web.grammarly.com✗ Missing
<script>static-web.grammarly.com✗ Missing
<script>static-web.grammarly.com✗ Missing
<script>static-web.grammarly.com✗ Missing
<script>static-web.grammarly.com✗ Missing
<script>static-web.grammarly.com✗ Missing
<script>static-web.grammarly.com✗ Missing
<script>static-web.grammarly.com✗ Missing
<script>static-web.grammarly.com✗ Missing
<script>static-web.grammarly.com✗ Missing
<script>googleads.g.doubleclick.net✗ Missing
<script>googleads.g.doubleclick.net✗ Missing
<script>bat.bing.com✗ Missing
<link>accounts.google.com✗ Missing
<script>transcend-cdn.com✗ Missing
<script>j.6sc.co✗ Missing
<script>js.adsrvr.org✗ Missing
<script>js.zi-scripts.com✗ Missing
F
Email Security
Action
No DMARC
FIX
No DMARC
Warning::
No DMARC record found
Without DMARC, email receivers have no policy for handling authentication failures.
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.

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

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
Security Headers
6 of 10 headers properly configured
REVIEW
6 of 10 headers properly configured
Info::
Strict-Transport-Security is properly configured (consider adding preload)
Got: max-age=31536000; includeSubDomains
Info::
X-Content-Type-Options is properly configured
Got: nosniff
Warning::
X-Frame-Options header is missing
This header prevents clickjacking by controlling who can embed your page in a frame. Set it to DENY or SAMEORIGIN.
Expected: DENY
Info::
Referrer-Policy is properly configured
Got: no-referrer-when-downgrade
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: frame-ancestors 'self' *.grammarly.com
Info::
Cross-Origin-Opener-Policy is set but not 'same-origin'
Got: same-origin-allow-popups 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

This header prevents clickjacking by controlling who can embed your page in a frame. Set it to DENY or SAMEORIGIN.

Expected: DENY
Why this matters

Without frame protection, your site can be embedded in a hostile page and used for clickjacking.

Learn more ▾

Clickjacking overlays your site under a transparent malicious page so users click invisible buttons. Setting X-Frame-Options: DENY (or a modern frame-ancestors CSP directive) blocks the embedding entirely. There's almost never a legitimate reason to allow it.

Source: OWASP / MDN

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

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

Expected: same-origin
Why this matters

COOP is set to a less-restrictive value (same-origin-allow-popups or unsafe-none) — partial isolation only.

Learn more ▾

COOP: same-origin is the strictest level. same-origin-allow-popups allows authenticated popup windows back to your origin. unsafe-none is the legacy default (effectively off). Pick the strictest level your app's popup flows tolerate.

Source: MDN COOP

B
Content Security Policy
2 of 10 CSP checks passed
REVIEW
2 of 10 CSP checks passed
Info::
Raw CSP policy
Got: frame-ancestors 'self' *.grammarly.com
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'
Info::
No script-src or default-src to check for 'unsafe-inline'
Info::
No script-src or default-src to check for 'unsafe-eval'
Info::
No script-src or default-src to check for wildcard
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'
Info::
frame-ancestors directive is set
Got: frame-ancestors 'self' *.grammarly.com
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

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

Parsed Policy

frame-ancestors 'self'*.grammarly.com
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
B
security.txt
Published with 1 contact(s)
REVIEW

security.txt

Contact: security@grammarly.com
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 136 days)
Got: 2026-08-21T23:59:59Z
Info::
Certificate chain has 3 certificates
Info::
Certificate uses modern signature algorithm
Got: SHA256-RSA
Info::
Certificate covers 2 domain(s)
Got: www.grammarly.com, grammarly.com
Info::
Certificate is issued by a trusted CA
Got: CN=Amazon RSA 2048 M02,O=Amazon,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=www.grammarly.comIssuer CN=Amazon RSA 2048 M02,O=Amazon,C=USValid 2025-07-23T00:00:00Z → 2026-08-21T23:59:59ZExpires in 136 days SANs www.grammarly.com, grammarly.comSignature SHA256-RSASerial 316b6347007b64e6f210e827de61381
Intermediate (CA Certificate)
Subject CN=Amazon RSA 2048 M02,O=Amazon,C=USIssuer CN=Amazon Root CA 1,O=Amazon,C=USValid 2022-08-23T22:25:30Z → 2030-08-23T22:25:30ZExpires in 1599 days Signature SHA256-RSASerial 773124a4bcbd44ec7b53beaf194842d3a0fa1
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 4285 days Signature SHA256-RSASerial 67f944a2a27cdf3fac2ae2b01f908eeb9c4c6
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
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)
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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