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HeadersMedium PriorityFree
X-Content-Type-Options header
This header prevents browsers from MIME-sniffing a response away from the declared content-type, stopping certain attack vectors.
Why It Matters
Without nosniff, browsers might interpret files differently than intended, potentially executing malicious content. This is especially dangerous for user-uploaded files.
How We Check
We verify the presence of `X-Content-Type-Options: nosniff` header on your responses.
How to Fix
Add the header: X-Content-Type-Options: nosniff. This should be set on all responses and has no drawbacks.
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