Header Shield

Inspect security headers and understand configuration risks. Guidance only, not a penetration test.

Header Shield is a client-side utility designed to evaluate HTTP response headers for potential security configuration gaps. It passively analyzes page headers as you browse, highlighting missing protections and showcasing opportunities to strengthen your server configuration. How to Use: 1. Scan on Load: Click the Header Shield extension icon in your toolbar to instantly evaluate the active tab's HTTP response headers. 2. Review Details: Expand any finding to view the status, risk summary, and copyable header configuration examples. 3. Compare Environments: Go to the extension's options page, save reports for multiple sites (e.g., staging and production), and compare their configurations side-by-side. 4. Clean Up Noise: Ignore passing or accepted findings per-origin so they do not clutter future scans. 5. Debug Requests: Open Chrome Developer Tools, switch to the "Header Shield" panel, and reload the page to inspect and analyze individual asset or API requests on-demand. Key Features: • Passive Header Analysis: Instantly reviews the active webpage's response headers upon opening the extension popup. • DevTools Network Scanner: Includes a custom DevTools panel to inspect and review individual network requests, API responses, or subresource calls. • Configuration Audit: Evaluates key defensive policies including Content Security Policy (CSP), HTTP Strict Transport Security (HSTS), CORS rules, cross-origin isolation policies (COOP/COEP/CORP), Referrer-Policy, and cookie security attributes. • Side-by-Side Diff: Compare saved reports from different endpoints or deployment environments (such as staging and production) to spot configuration drift. • Local Privacy: All analysis runs entirely in your browser. No response headers or page data are sent to external servers, and cookie values are never displayed or stored. • Export Options: Save findings locally or export reports to Markdown or JSON formats for offline review. Disclaimer: Header Shield provides configuration guidance based on observed HTTP response headers. It is not a vulnerability scan or security certification. Findings should be reviewed by a qualified security professional.