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WordPress fix guide

Cross-Origin Isolation Headers Not Configured on WordPress

One or more cross-origin isolation headers (COOP, COEP, CORP) are not set. These headers provide defense-in-depth but are only required if your site uses features like SharedArrayBuffer or needs strict cross-origin isolation.

Issue ID: SEC-CROSS-ORIGIN-ISOLATION-001Severity: advisoryEffort: S

Why this matters

One or more cross-origin isolation headers (COOP, COEP, CORP) are not set. These headers provide defense-in-depth but are only required if your site uses features like SharedArrayBuffer or needs strict cross-origin isolation. This affects browser trust signals and whether visitors feel safe submitting contact details.

WordPress fix path

How to fix this on WordPress

Use the page editor, theme, or SEO tooling depending on where this issue lives.

  1. 1Inspect the page and theme output.
  2. 2Apply the fix in the most direct place.
  3. 3Publish and validate with a re-audit.

After you fix it

  • ✓Confirm all three cross-origin headers are present in response headers

Same fix, other platforms

Fix cross-origin isolation headers not configured on a different CMS

Other fixes

More WordPress fixes

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