DevMeth
C20

Public web surface

Wide-Open CORS Check — Can Any Site Read Your Responses with Your Cookies?

DevMeth checks the 48 known AI-code failure patternsnot a penetration test or a security guarantee.

What the issue is

A response that allows any origin (Access-Control-Allow-Origin: *) together with cookies lets any website's scripts send credentialed requests to your app and read the responses.

Why AI tools generate it

AI tools set permissive CORS headers so a demo works from anywhere, and the wildcard-plus-credentials combination is a classic generated mistake.

How DevMeth detects it

A read-only live probe issues a preflight to your endpoints and checks whether the response combines a wildcard allow-origin with credentials.

C20
What a finding looks like
High

Your site tells any website's scripts it can send requests with your cookies

WHAT WE FOUND

response headerAccess-Control-Allow-Origin: *

Sample — illustrative and masked exactly as a real report shows it. Run a free scan to see your own results.

The fix, in three steps

Restrict Access-Control-Allow-Origin to specific trusted origins and never combine a wildcard with credentials. Three steps.

Run a free scan and each finding carries a paste-ready fix prompt you can act on.

Try a free scan

FAQ

Why is * with credentials dangerous?

It lets any website's script send requests carrying your user's cookies and read the responses — cross-site data exfiltration.

How is this probed?

A read-only preflight request checks your endpoint's CORS response for a wildcard allow-origin combined with credentials.

What's the fix?

Restrict allow-origin to explicit trusted origins and keep credentials working with those specific origins, never a wildcard.

DevMeth checks the 48 known AI-code failure patternsnot a penetration test or a security guarantee. A clear result means each known pattern was checked and found clear or not applicable for your app; it is not a guarantee of security.