Checks

CORS reflects an untrusted Origin

The response copied the scanner's Origin, https://security-check.invalid, into Access-Control-Allow-Origin.

Why it matters

Any website can send its own Origin and be echoed back, so any site can read the response. If credentials are allowed, that includes credentialed data.

What to do

Allowlist trusted origins. Do not reflect the request Origin, and do not combine a reflected origin with Allow-Credentials: true.

Reference

CORS controls which origins may read responses and must not expose credentialed data broadly.

MDN — Cross-Origin Resource Sharing (CORS)