YesWiki's Bazar widget handler reflects the "id" "GET" parameter into HTML attributes using "strip_tags()" only. Because "strip_tags()" does not escape double quotes, an attacker can break out of the attribute value, inject an event handler such as "onmouseover", and execute arbitrary JavaScript in the victim's browser. This issue is reachable without authentication. During validation, the vulnerable "widget" route returned the injected HTML for both "/HomePage/widget?id=..." and "/NoSuchPage/widget?id=...", which shows that no login, no page ownership, no edit rights, and not even a valid page tag were required. The only routing prerequisite observed was that the Bazar extension is enabled and the request includes an "id" parameter.