According to WikiPedia
Cross-site scripting is a type of computer security vulnerability typically found in web applications. XSS enables attackers to inject client-side scripts into web pages viewed by other users. A cross-site scripting vulnerability may be used by attackers to bypass access controls such as the same-origin policy.
Xssizer helps penetration tester, bug hunters and other security professionals to easily detect such vulnerabilities and produces a ready-to-use PoC exploit for demostration.
Installation
Then open localhost/xssizer/pro.php in your browser.
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