security_defaults.conf

    # config to not allow the browser to render the page inside an frame or iframe
    # and avoid clickjacking http://en.wikipedia.org/wiki/Clickjacking
    add_header X-Frame-Options SAMEORIGIN;

    # when serving user-supplied content, include a X-Content-Type-Options: nosniff header along with the Content-Type: header,
    # to disable content-type sniffing on some browsers.
    # https://www.owasp.org/index.php/List_of_useful_HTTP_headers
    add_header X-Content-Type-Options nosniff;

    # This header enables the Cross-site scripting (XSS) filter built into most recent web browsers.
    # It's usually enabled by default anyway, so the role of this header is to re-enable the filter for
    # this particular website if it was disabled by the user.
    # https://www.owasp.org/index.php/List_of_useful_HTTP_headers
    add_header X-XSS-Protection "1; mode=block";

    # config to enable HSTS(HTTP Strict Transport Security) https://developer.mozilla.org/en-US/docs/Security/HTTP_Strict_Transport_Security
    # to avoid ssl stripping https://en.wikipedia.org/wiki/SSL_stripping#SSL_stripping
    add_header Strict-Transport-Security "max-age=31536000; includeSubdomains;";