Element Code: SE-008
Quick Reference
Issue: X-XSS-Protection header not set
Impact: Older browsers lack built-in XSS filtering
Fix: Add X-XSS-Protection: 1; mode=block
Detection: HTTP header inspection
What Is This Issue?
While modern browsers have deprecated this header in favor of CSP, older browsers still benefit from the built-in XSS filter it enables.
Why This Matters for Your Website
Legacy protection for older browsers. Modern sites should rely on CSP, but this provides backward compatibility.
How to Fix This Issue
- Add header: X-XSS-Protection: 1; mode=block
- Prioritize CSP: This is supplementary, not primary protection
Tools for Detection
- Security headers check: Verify X-XSS-Protection
TL;DR (The Simple Version)
Add X-XSS-Protection header for older browser protection. For modern browsers, focus on Content-Security-Policy instead.
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