Set object-src to 'none' on nginx
Why it matters
Without a restrictive object-src, object and embed tags can load content from any source. Hardly any site still needs plugins, so blocking them is usually free.
Staged change. Do this in stages and check each one before the next, so a mistake does not break your site or your mail.
The fix
- Stage 1: check for object or embed tags on your pages (PDF viewers use them).
- Stage 2: append ; object-src 'none' to the value of the add_header Content-Security-Policy line, run sudo nginx -t and reload.
Related
- Reported by the Content-Security-Policy check
- Add a Content-Security-Policy
- Enforce the report-only Content-Security-Policy
- Send the Content-Security-Policy as an HTTP header
- Restrict where scripts can load from
- Replace 'unsafe-inline' scripts with nonces or hashes
- Remove 'unsafe-eval' from script-src
- Remove wildcard sources from script-src
- Add base-uri to the Content-Security-Policy
- Reduce reliance on inline styles
- Fix the Content-Security-Policy syntax
Scan your domain to see whether this applies to you.