~/tools / security-headers
Security Headers Checker
Scan HTTP security headers. Grades HSTS, CSP, X-Frame-Options and others, with explanations of what each header protects.
[ WARNING ]
Decent but improvable (52/100) — missing: X-Frame-Options, Permissions-Policy · weak: strict-transport-security
── output ─────
52
security_score
HTTP 403 · https://sainsburys.co.uk
Strict-Transport-Security (HSTS)
[ WEAK ]
// Forces HTTPS for all connections. Prevents downgrade attacks.
max-age=86400 ; includeSubDomains
Content-Security-Policy (CSP)
[ STRONG ]
// Defines which sources of scripts/styles/images are allowed. Prevents XSS.
frame-ancestors 'self' https://t.contentsquare.net https://r.contentsquare.net https://uxanalytics.content-square.fr https://app.contentsquare.com https://nectar360.citrusad.com https://nectar360-eu-sandbox.citrusad.com https://campaign.citrusad.com https://testers.sainsburys.co.uk https://demo3.citrusad.com; report-uri https://sainsburys.co.uk/csp-report
X-Frame-Options
[ MISSING ]
// Prevents clickjacking by blocking iframe embedding from other origins.
// missing — add this header to improve security
X-Content-Type-Options
[ STRONG ]
// Prevents MIME sniffing. Should be 'nosniff'.
nosniff
Referrer-Policy
[ PRESENT ]
// Controls how much referrer info is leaked when navigating away.
strict-origin-when-cross-origin
Permissions-Policy
[ MISSING ]
// Restricts which browser features (camera, mic, etc.) the page can use.
// missing — add this header to improve security