Cross-Site Scripting (XSS) is a web application vulnerability in which an attacker causes a browser to run untrusted script in the context of a trusted site. The acronym XSS is commonly used in security, IT, audit, and compliance work.
Cross-Site Scripting (XSS) is important in secure software development, application testing, DevSecOps, and vulnerability management because design and code choices can directly affect security risk.