Headers Security
low Severity
Free Check

Content-Type Header & Charset Declaration

Ensures all HTML/API responses specify an explicit Content-Type with charset=utf-8 to prevent UTF-7 encoding bypasses.

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Why It Matters

Omitting charset declarations can allow legacy encoding attacks where UTF-7 payloads bypass input filters.

How We Check This

We check that responses return Content-Type: text/html; charset=utf-8 or application/json; charset=utf-8.

How to Fix & Implement

Copy-paste configuration blocks tailored for your web server or edge proxy.

nginx snippet
charset utf-8;

Frequently Asked Questions

Why is UTF-7 an issue?

UTF-7 represents angle brackets and quotes without standard characters, historically bypassing basic XSS filters.