WebForensik

A Content Security Policy (CSP) is a doorkeeper rule for the browser: "Scripts and styles may only be loaded from these allowed sources." Without CSP, injected malicious code (XSS) can freely fetch anything. Start with a simple, secure baseline.

Apache server (classic hosting at most providers)

File: .htaccess in the web root

<IfModule mod_headers.c>
    Header always set Content-Security-Policy "default-src 'self'; img-src 'self' data: https:; style-src 'self' 'unsafe-inline'; script-src 'self' 'unsafe-inline'; font-src 'self' https: data:; object-src 'none'; frame-ancestors 'self'; base-uri 'self'"
</IfModule>

⚠ This policy is intentionally pragmatic (allows inline styles since many themes/plugins rely on them). If something breaks after enabling: F12 → Console shows "Refused to load…" — add the affected domain after script-src / img-src.

# BEGIN WebForensik CSP
<IfModule mod_headers.c>
    Header always set Content-Security-Policy "default-src 'self'; img-src 'self' data: https:; style-src 'self' 'unsafe-inline'; script-src 'self' 'unsafe-inline'; font-src 'self' https: data:; object-src 'none'; frame-ancestors 'self'; base-uri 'self'"
</IfModule>
# END WebForensik CSP

add_action('send_headers', function () {
    header("Content-Security-Policy: default-src 'self'; img-src 'self' data: https:; style-src 'self' 'unsafe-inline'; script-src 'self' 'unsafe-inline'; font-src 'self' https: data:; object-src 'none'; frame-ancestors 'self'; base-uri 'self'");
});

✓ How to verify it works: Open page, F12 → Console — no red "Refused to load…" messages. Network tab → first request → Response Header "content-security-policy" visible.

Permissions-Policy controls whether scripts (including third-party) may access camera, microphone, location, motion sensors etc. GDPR-relevant because sensitive device APIs can otherwise be reached unnoticed.

Apache server (classic hosting at most providers)

File: .htaccess in the web root

<IfModule mod_headers.c>
    Header always set Permissions-Policy "camera=(), microphone=(), geolocation=(), payment=(), usb=(), accelerometer=(), gyroscope=(), magnetometer=(), interest-cohort=()"
</IfModule>

⚠ "()" at the end means: no caller (not even your own page) may use this API. If you need geolocation (e.g. a map feature): use geolocation=(self) instead of geolocation=(). "interest-cohort=()" disables Google’s FLoC tracking.

<IfModule mod_headers.c>
    Header always set Permissions-Policy "camera=(), microphone=(), geolocation=(), payment=(), usb=(), interest-cohort=()"
</IfModule>

add_action('send_headers', function () {
    header('Permissions-Policy: camera=(), microphone=(), geolocation=(), payment=(), usb=(), interest-cohort=()');
});

✓ How to verify it works: F12 → Network → Response Header: "permissions-policy" visible.

Cookies without the "Secure" flag are also sent over unencrypted HTTP — and can be intercepted by anyone on the same WLAN. There’s no reason to omit Secure on HTTPS-only sites.

Apache server (classic hosting at most providers)

File: .htaccess in the web root

<IfModule mod_headers.c>
    Header always edit Set-Cookie "^(.*)$" "$1; Secure" "expr=!(resp('Set-Cookie') -strmatch '*Secure*')"
</IfModule>

⚠ This header appends "; Secure" to cookies that don’t have it yet. Requires Apache 2.4+. The cleaner fix is to correct the code that sets the cookie (PHP: session.cookie_secure=1 in php.ini, or setcookie() with "secure" => true).

add_filter('secure_logged_in_cookie', '__return_true');
add_action('init', function () {
    if (!headers_sent()) {
        @ini_set('session.cookie_secure', '1');
        @ini_set('session.cookie_httponly', '1');
        @ini_set('session.cookie_samesite', 'Lax');
    }
});

✓ How to verify it works: F12 → Application → Cookies → your-domain.com. The "Secure" column should show a checkmark for every cookie.

Without "SameSite" cookies are sent on requests from foreign sites — the basis of CSRF attacks (a foreign page silently triggers actions in your name because the login cookie travels along). Set SameSite=Lax as a minimum.

Apache server (classic hosting at most providers)

File: .htaccess in the web root

<IfModule mod_headers.c>
    Header always edit Set-Cookie "^(.*)$" "$1; SameSite=Lax" "expr=!(resp('Set-Cookie') -strmatch '*SameSite*')"
</IfModule>

⚠ SameSite=Lax is a good default. Strict is safer but breaks external links (user clicks from Google to your site — cookies are NOT sent, login is lost). None allows cross-site but requires "; Secure".

@ini_set('session.cookie_samesite', 'Lax');
@ini_set('session.cookie_secure', '1');
@ini_set('session.cookie_httponly', '1');

✓ How to verify it works: F12 → Application → Cookies → "SameSite" column should show "Lax" or "Strict" everywhere, not empty.

CAA records (Certification Authority Authorization) define in DNS which Certificate Authorities are allowed to issue certificates for your domain. Without a CAA record an attacker could request a fraudulent certificate for your domain at any CA. CAA is pure DNS configuration — set in your registrar/DNS-panel, NOT in WordPress.

Name   Type   Flag   Tag      Value
@      CAA    0      issue    "digicert.com"
@      CAA    0      issue    "letsencrypt.org"
@      CAA    0      iodef    "mailto:security@your-domain.com"

✓ How to verify it works: On https://www.ssllabs.com/ssltest/analyze.html?d=your-domain.com → "DNS CAA" section → all your CAs should be listed. Or via dig: dig CAA your-domain.com.

DMARC combines SPF and DKIM into an explicit instruction for receiving mail servers: "What to do if emails claim to come from us but SPF/DKIM fail?" Without DMARC each server decides — usually generously. With DMARC=reject you effectively prevent phishing in your name.

✓ How to verify it works: dig TXT _dmarc.your-domain.com — or online https://dmarcian.com/dmarc-inspector/.

A security.txt (RFC 9116) tells security researchers how to responsibly report vulnerabilities to you. Without it, reports may go to spam or never be sent. A plain text file at the correct path is enough.

Apache server (classic hosting at most providers)

File: /.well-known/security.txt (create the folder if it doesn’t exist)

Contact: mailto:security@your-domain.com
Expires: 2027-12-31T23:59:59.000Z
Preferred-Languages: en, de
Canonical: https://your-domain.com/.well-known/security.txt

⚠ Replace "security@your-domain.com" with your actual security contact (or a generic info@). "Expires" must be a future date and should be renewed regularly. The file is plain .txt, not PHP.

Contact: mailto:security@your-domain.com
Expires: 2027-12-31T23:59:59.000Z
Preferred-Languages: en, de
Canonical: https://your-domain.com/.well-known/security.txt

✓ How to verify it works: Open https://your-domain.com/.well-known/security.txt in a browser — content must be visible (no 404).