Browser & Web Performance · Middle · Question 56 of 75

What does `X-Content-Type-Options: nosniff` do?

1Disables content compression
✓Correct answer: Stops the browser from guessing the MIME type, so e.g. a text file can't be executed as a script
3Hides the server software version

Explanation

MIME sniffing could turn an uploaded file into executable script or style. With nosniff the declared Content-Type is respected.

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