Description
Cross-site Scripting (XSS) refers to client-side code injection attack wherein an attacker can execute malicious scripts into a legitimate website or web application. XSS occurs when a web application makes use of unvalidated or unencoded user input within the output it generates.
Remediation
Apply context-dependent encoding and/or validation to user input rendered on a page
References
Cross-site Scripting (XSS) Attack - Acunetix
XSS Filter Evasion Cheat Sheet
Excess XSS, a comprehensive tutorial on cross-site scripting
Related Vulnerabilities
WordPress Plugin Blog Designer Cross-Site Scripting (1.8.11)
WordPress Plugin Simple Banner Cross-Site Scripting (2.10.3)
WordPress Plugin Slimstat Analytics Cross-Site Scripting (3.9.1)
WordPress Plugin bbPress Cross-Site Scripting (2.5.9)
WordPress Plugin WooCommerce Subscriptions Cross-Site Scripting (2.6.2)