Cross-User Defacement

Description
An attacker can make a single request to a vulnerable server that will cause the sever to create two responses, the second of which may be misinterpreted as a response to a different request, possibly one made by another user sharing the same TCP connection with the sever. This can be accomplished by convincing the user to submit the malicious request themselves, or remotely in situations where the attacker and the user share a common TCP connection to the server, such as a shared proxy server. In the best case, an attacker can leverage this ability to convince users that the application has been hacked, causing users to lose confidence in the security of the application. In the worst case, an attacker may provide specially crafted content designed to mimic the behavior of the application but redirect private information, such as account numbers and passwords, back to the attacker.

Related Attacks
HTTP Response Splitting

Related Vulnerabilities
Category:Input Validation Vulnerability

Related Countermeasures
Category:Input Validation