Vishwa

vishvega

HeaderShield adds a conservative set of security headers that improve browser protection without breaking most sites. It also provides optional strict cross-origin protections for sites that are ready for them.
Default headers include:
<ul>
<li>X-Frame-Options</li>
<li>X-Content-Type-Options</li>
<li>X-XSS-Protection (legacy)</li>
<li>Referrer-Policy</li>
<li>Permissions-Policy</li>
<li>Content-Security-Policy (upgrade-insecure-requests)</li>
<li>Strict-Transport-Security (HTTPS only)</li>
</ul>
Strict Mode can additionally enable COEP, COOP, and CORP for stronger isolation, but may break third‑party scripts or embeds. Use with care and test on staging first.
<h4>Source code for third-party assets</h4>
The admin UI uses SlimSelect for the multi-select dropdown. Human-readable source is included in the plugin:
<ul>
<li>JavaScript: <code>assets/js/slimselect.js</code> (minified build: <code>assets/js/slimselect.min.js</code>)</li>
<li>CSS: <code>assets/css/slimselect.css</code> (minified build: <code>assets/css/slimselect.min.css</code>)</li>
</ul>
Upstream project: https://github.com/brianvoe/slim-select (MIT). This plugin does not use a custom build process; the included files are from the published release.

HeaderShield

Add safe, modern HTTP security headers with optional strict cross-origin protections and a simple admin UI.

Jay Suthar

BoundaryGuard Headers enforces modern HTTP security headers to harden your WordPress site against XSS, clickjacking, mixed content, and cross-origin attacks.
Key Features:
<ul>
<li>Essential Protection: Adds X-Frame-Options, X-Content-Type-Options, Referrer-Policy, and Permissions-Policy to reduce attack surface and prevent clickjacking.</li>
<li>HSTS (Strict Transport Security): Forces HTTPS connections to help prevent protocol downgrade and man-in-the-middle attacks.</li>
<li>Advanced Isolation (COOP/COEP): Enables Cross-Origin-Opener-Policy and Cross-Origin-Embedder-Policy to improve cross-origin isolation and mitigate certain side-channel attacks.</li>
<li>Content Security Policy (CSP): One of the strongest defenses against XSS. Includes a dashboard-based CSP builder with preset options to whitelist trusted sources for scripts, styles, images, and more.</li>
<li>CSP Report-Only Mode: Test your policy safely without blocking content.</li>
<li>Server Header Hardening: Removes or limits exposure of headers such as <code>X-Powered-By</code> and <code>Server</code>.</li>
<li>Lightweight and Fast: Uses PHP headers for broad server compatibility and minimal performance impact.</li>
<li>No <code>.htaccess</code> Editing Required: Works without modifying server configuration files.</li>
</ul>
Designed for developers and site owners who want stronger security without unnecessary complexity.
<h3>External Services</h3>
This plugin provides a Content Security Policy (CSP) builder. To assist users, it includes “Preset Buttons” that allow users to quickly add domain names to their own CSP whitelist.
This plugin DOES NOT connect to, load data from, or send data to these services automatically. The following third-party domains are referenced as presets within the admin dashboard for whitelisting purposes: 
* Google Analytics (www.google-analytics.com) – Used for tracking whitelisting. [Privacy: https://policies.google.com/privacy] 
* Google Tag Manager (www.googletagmanager.com) – Used for tag management. [Privacy: https://policies.google.com/privacy] 
* Stripe (js.stripe.com, api.stripe.com) – Used for payment processing. [Privacy: https://stripe.com/privacy] 
* Facebook (www.facebook.com, connect.facebook.net) – Used for social embeds. [Privacy: https://www.facebook.com/policy.php] 
* YouTube (www.youtube.com, i.ytimg.com) – Used for video embeds. [Privacy: https://policies.google.com/privacy] 
* Vimeo (player.vimeo.com) – Used for video embeds. [Privacy: https://vimeo.com/privacy] 
* Gravatar (secure.gravatar.com) – Used for user avatars. [Privacy: https://automattic.com/privacy/]

BoundaryGuard Headers

Automatically enforces essential HTTP security headers to protect your site from XSS, clickjacking, and protocol downgrade attacks.

HeaderShield vs BoundaryGuard Headers