Fix · Express / Node
Fix “MIME-sniffing protection” on Express / Node
Add: X-Content-Type-Options: nosniff
res.setHeader("X-Content-Type-Options", "nosniff");Verify the fix
Re-run the MIME-sniffing protection check after deploying. Test config changes in staging first and keep a rollback: a wrong header can break a site faster than a missing one.
Other stacks: nginx · Apache · Caddy · Cloudflare