Missing X-Content-Type-Options header

Opportunity severity, in the Security tab

Why it matters

Without nosniff, browsers may interpret files as a different MIME type, enabling some attacks.

How to fix it

Add the header X-Content-Type-Options: nosniff.

How Crawlune finds it

Crawlune flags Missing X-Content-Type-Options header automatically on every crawl and lists the affected URLs under the Security tab, where you can filter, inspect each page and export the list to CSV. The free version crawls up to 550 URLs with every check enabled.