Security fix guide
Missing X-Content-Type-Options Header
Without X-Content-Type-Options: nosniff, browsers may MIME-sniff responses away from the declared content type, enabling attacks.
Issue ID: SEC-XCTO-001
Severity: medium
Impact: Low
Effort: S
Use this article when
- You need deeper remediation guidance than the issue card can show.
- You want CMS-specific steps before handing the fix to a developer.
- You want a repeatable re-check path after shipping the change.
What this issue is
Without X-Content-Type-Options: nosniff, browsers may MIME-sniff responses away from the declared content type, enabling attacks.
Why it matters
Without X-Content-Type-Options: nosniff, browsers may MIME-sniff responses away from the declared content type, enabling attacks. This affects browser trust signals and whether visitors feel safe submitting contact details.
How we detect it
- FreeSiteAudit flags this issue when the rule for SEC-XCTO-001 fails and the page evidence points to Http headers.
- You can usually confirm this by checking the page source or the relevant page settings inside your CMS.
Evidence examples
Check the affected page source, rendered output, or relevant CMS setting to confirm the missing or incorrect element.
How to fix it
- 1Add X-Content-Type-Options: nosniff to all server responses
- 2This is a one-line configuration in most web servers (Apache, Nginx, IIS)
How to re-check it
- Check response headers for X-Content-Type-Options: nosniff
Related tools
This issue is best verified with the full FreeSiteAudit crawl rather than a single-point mini tool.