Watcher is a Web security testing tool and passive vulnerability scanner. Watcher detects Web-application security issues as well as operational configuration issues. It looks for issues related to mashups, user-controlled payloads (potential XSS), cookies, comments, HTTP headers, SSL, Flash, Silverlight, referrer leaks, information disclosure, Unicode, and more. Watcher provides pen-testers hot-spot detection for vulnerabilities, developers quick sanity checks, and auditors PCI compliance auditing.
Source: https://thehackernews.com/2011/02/watcher-v151-web-security-testing-tool.html