Emerald Red Team

ERT-ACCESS-008

CORS reflects any origin with credentials

HighA01:2025CWE-942

Why it matters

Any website can make logged-in requests to your API and read the answers.

How to fix it

Allow only your own origins in Access-Control-Allow-Origin, never reflect the request's Origin with credentials.

How we test it

Passive — runs in the free check, looks only at what a browser can see.

Does your app have this problem?

The free Quick Check tests for it.

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