Dries Buytaert

Explanation

Identifies the software used by the origin server to handle the request (e.g. Apache, Nginx, Cloudflare).
Warning The server header exposes a specific version number (1.22.1). This makes it easier for attackers to find known vulnerabilities for that version. Remove or suppress the version number.

The date and time at which the request was made. A browser uses it for age calculations rather than using its own internal date and time; e.g. when comparing against Max-Age or Expires.

The type of the message body, specified as a MIME type.

A cookie that was sent from the server to the browser.
expires= sets the maximum lifetime of the cookie using a specific date.
max-age= sets the maximum lifetime of the cookie in seconds.
path= indicates the path that must exist in the requested URL for the browser to send the cookie.
Warning This cookie is missing the secure flag. Without it, the cookie can be sent over unencrypted HTTP connections, making it vulnerable to interception.
Notice This cookie is missing the httponly flag. Without it, JavaScript can access the cookie, increasing the risk of cross-site scripting (XSS) attacks.
Notice This cookie does not set an explicit samesite attribute. Browsers default to lax, but setting it explicitly is recommended for clarity and cross-browser consistency.

A cookie that was sent from the server to the browser.
path= indicates the path that must exist in the requested URL for the browser to send the cookie.
httponly forbids JavaScript from accessing the cookie. Helps mitigate the risk of client side scripts accessing a protected cookie.
Warning This cookie is missing the secure flag. Without it, the cookie can be sent over unencrypted HTTP connections, making it vulnerable to interception.
Notice This cookie does not set an explicit samesite attribute. Browsers default to lax, but setting it explicitly is recommended for clarity and cross-browser consistency.

Notice P3P stands for Platform for Privacy Preferences. P3P was abandoned by the W3C in 2018 and was never supported by any browser other than Internet Explorer. This header can be safely removed.

Some of the software used to generate or serve this page.

This Expires date is in the past: the page is considered stale and will be removed from all caches.
Notice The Cache-Control header, introduced in HTTP/1.1, supersedes the Expires header. Use a Cache-Control header with a max-age directive instead of Expires. Cache-Control is more powerful, but also more efficient in that it avoids roundtrips to the origin server.
PS: November 19th is my birthday! 🎂

no-cache means the response can be stored by any cache, but the stored response must be validated with the origin server before each reuse. If the origin confirms that the response hasn't changed, downloading of the full response body can be skipped.
Warning no-cache will cause a revalidation request to the origin server for every use of the cached response. Consider using public with appropriate max-age to improve caching efficiency.
Warning no-store means the response may not be stored in any cache, including the browser's cache.
must-revalidate indicates that once a page becomes stale, both shared caches and browser caches must not use their stale copy without validating it with the origin server first.
Notice It does not make sense to set must-revalidate with no-store; when nothing is cached, there is nothing to revalidate.
Notice It does not make sense to set must-revalidate with no-cache; must-revalidate is implied.
Notice no-store is set, so it does not make sense to set no-cache as well.

Warning Caches must revalidate with the origin server before serving the page. If the page is something everybody can access, this behavior is not desired.
Notice Pragma is an HTTP/1.0 header. In HTTP/1.1, Pragma is deprecated and superseded by the Cache-Control header. Remove Pragma to save bandwidth and processing power.

The X-Content-Type-Options header, when set to nosniff, prevents MIME type sniffing. This enhances security by ensuring browsers respect the declared Content-Type of the response, mitigating MIME confusion attacks.
The value nosniff is correctly set, providing protection against MIME type sniffing attacks.

The Strict-Transport-Security header (HSTS) instructs browsers to only use HTTPS for future connections to this domain, enhancing security by preventing downgrade attacks and cookie hijacking.
max-age specifies the time, in seconds, that the browser should remember to use HTTPS only for this domain.

missing Add a Content-Security-Policy header. The Content-Security-Policy header helps browsers prevent cross site scripting (XSS) and data injection attacks.

missing Add a Referrer-Policy header. When a visitor navigates from one page to another, browsers often pass along referrer information. The Referrer-Policy header controls how much referrer information a browser can share. This is important to configure when private information is embedded in the path or query string and passed onto an external destination.

missing Add a Permissions-Policy header. Restrict access to device features like the camera, microphone, location, accelerometer and much more.

missing Add a Cross-Origin-Embedder-Policy to specify how this page can be loaded by cross-origin resources.

missing Add a Cross-Origin-Opener-Policy header to opt-in into better browser isolation.

missing Add a Cross-Origin-Resource-Policy header to specify who can load this page.

missing Add a X-Frame-Options header. The X-Frame-Options header prevents this URL from being embedded in an iframe. This protects against clickjacking attacks. Alternatively, set a Content-Security-Policy header with a frame-ancestors directive.

missing Add a X-Permitted-Cross-Domain-Policies header to prevent Flash, Adobe Reader and other clients from sharing data across domains.