Protect yourself from malicious exploitation via MIME sniffing.
MIME-Type sniffing explained
Internet Explorer and Chrome browsers have a feature called "MIME-Type sniffing" that automatically detects a web resource's type. This means, for example, that a resource identified as an image can be read as a script if its content is a script.
This property allows a malicious person to send a file to your website to inject malicious code. We advise you to disable the MIME-Type sniffing to limit such activity.
Chrome has been working on a feature called Site Isolation which provides extensive mitigation against exploitation of these types of vulnerabilities. Site Isolation is more effective when MIME types are correct.
How to prevent MIME-Type sniffing
Configure a "X-Content-Type-Options" HTTP header. Add the "X-Content-Type-Options" HTTP header in the responses of each resource, associated to the "nosniff" value. It allows you to guard against such misinterpretations of your resources.
https://www.justegeek.fr/proteger-un-peu-plus-son-site-avec-la-balise-x-content-type-options/
