XWiki Platform is a generic wiki platform. Prior to versions 4.10.19, 15.5.4, and 15.10-rc-1, parameters of UI extensions are always interpreted as Velocity code and executed with programming rights. Any user with edit right on any document like the user's own profile can create UI extensions. This allows remote code execution and thereby impacts the confidentiality, integrity and availability of the whole XWiki installation. This vulnerability has been patched in XWiki 14.10.19, 15.5.4 and 15.9-RC1. No known workarounds are available.

XWiki Platform remote code execution from account through UIExtension parameters