Hack with confidence.
Page user-poll.php is vulnerable to at least the following:
Insufficent Transport Layer Protection: This page is vulnerable to interception with wireshark or tcpdump.
Method Tampering: Because the page does not specify that the input parameters must be posted, it is possible to submit input parameters via a post or a get. This is a second order vulnerability allowing other vulnerabilities to be exploited easier.
HTTP Parameter Pollution: If multiple parameters with the same name are sent in a request, different application servers will react differently. PHP takes only one of the parameters but not neccesarily the parameters intended by the developer. By duplicating parameters with a value of your choosing and placing that parameters before and-or after the pages native parameters, you can influence the pages behavior. Note that ASP and Java application servers act different.
Cross Site Request Forgery: This page is vulnerable to cross-site request forgery. There are a few steps to prepare a cross-site script to carry out the cross-site request forgery. Begin by filling out the form capturing the legitimate request. Inject a stored or reflected cross-site script anywhere on the site that will cause the browser to submit a copy of the legitimate request to the server. The server will process the request as if the user had filled out the form themselves.
HTML Injection: It is possible to inject your own HTML into this page because the input is not encoded prior to be used as output. Determine which input field contributes output here and inject HTML, CSS, and/or Javascripts in order to alter the client-side code of this page.
SQL Injection with SQLMap: This page contains an sql injection vulnerability. The SQLMap tool may be able to automate testing and confirming this vulnerability.
SQL Injection: Attempt to inject special database characters or SQL timing attacks into page parameters. Database errors, page defacement, or noticable delays in response may indicate SQL injection flaws. This page is vulnerable.
Reflected Cross-Site Scripting: This page is vulnerable to reflected cross-site scripting because the input is not encoded prior to be used as output. Determine which input field contributes output here and inject scripts. Try to redirect the user to the capture-data.php page which records cookies and other parameters. Visit the captured-data.php page to view captured data.