Sec,fetch,site:,cross,site -

: The browser adds sec-fetch-site: cross-site and sec-fetch-mode: navigate (or cors ).

This looks like you're piecing together the technical components of , specifically those used for Cross-Origin Resource Sharing (CORS) and Cross-Site Request Forgery (CSRF) protection. The Concept: Fetch Metadata ( sec-fetch-* ) sec,fetch,site:,cross,site

: The server sees cross-site on a sensitive POST action and rejects it because it knows this request didn't originate from its own trusted frontend. Summary of the Headers sec,fetch,site:,cross,site

— Indicates the "where" (different domain). sec,fetch,site:,cross,site

— Indicates the "what" (data fetch, not an image or script).

: This indicates the request originated from a completely different website (e.g., attacker.com trying to fetch data from yourbank.com ). Value: same-origin : The request started on your own site.