All current versions of jQuery Mobile (JQM) as of 2019-05-04 are vulnerable to DOM-based Cross-Site Scripting (XSS) via crafted URLs. In JQM versions up to and including 1.2.1, the only requirement is that the library is included in a web application. In versions > 1.2.1, the web application must also contain a server-side API that reflects back user input as part of an HTTP response of any type. Practically all non-trivial web applications contain at least one such API.
Additionally, all current versions of JQM contain a broken implementation of a URL parser, which can lead to security issues in affected applications.