All-in-one free web application security tool. Web application vulnerability and privacy scanner with support for HTTP cookies, Flash, HTML5 localStorage, sessionStorage, CANVAS, Supercookies, Evercookies. Includes a free SSL/TLS, HTML and HTTP vulnerability scanner and URL malware scanner.

Ruby on Rails 3 is using a CookieStore feature for session management which can result in various vulnerabilities, as described here and here. While it's not guaranteed that these websites are vulnerable or even use Ruby, the cookie name pattern resembles the one used by CookieStore.