CORS Checker
Check a URL's CORS headers and detect dangerous configurations like Access-Control-Allow-Origin: * with credentials.
CORS is the single most-abused misconfiguration on modern APIs — a wildcard origin combined with credentials effectively hands your authenticated session data to any website on the internet. This checker sends both simple and preflight requests and flags the exact combinations that browsers and pentesters treat as critical findings.
CORS Checker evaluates the following signals from your target host:
Frequently asked questions
- Yes — we send both simple and preflight requests.
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