Typical severity: Very High. Likelihood of attack: High. This type of attack is a form of Cross-Site Scripting (XSS) where a malicious script is "reflected" off a vulnerable web application and then executed by a victim's browser. The process starts with an adversary delivering a malicious script to a victim and convincing the victim to send the script to the vulnerable web application.
Use browser technologies that do not allow client-side scripting. | Utilize strict type, character, and encoding enforcement. | Ensure that all user-supplied input is validated before use.