A malicious script is injected in web application and is permanently stored on the server. When a user requests some
information from server, injected script is reflected by a server as an error message or search result. These types of
attacks are more serious than other types because an attacker injects a script once and affect a large number of users.
Attacker tricks the user to click on the link that contains malicious code. If the malicious script is stored in the server
database then a user becomes a victim by viewing the page without clicking on any link. Here some examples of real
world persistent attacks. The Indian security researcher ShubhamUpadhyaya found a new permanent XSS on 13
November 2012 that affected the products listings on ebay.com (KF)