Adobe Experience Manager versions 6.5.21 and earlier are affected by a DOM-based Cross-Site Scripting (XSS) vulnerability that could allow an attacker to execute arbitrary code in the context of the victim's browser. This issue occurs when data from a user-controllable source is improperly sanitized before being used in the Document Object Model (DOM) of a web page, leading to the execution of malicious scripts. Exploitation of this issue requires user interaction, such as tricking a victim into clicking a link or navigating to a malicious website.