XWiki Platform is a generic wiki platform. Starting in versions 2.2-milestone-1 and prior to versions 14.4.8, 14.10.4, and 15.0-rc-1, it's possible to execute javascript with the right of any user by leading him to a special URL on the wiki targeting a page which contains an attachment. This has been patched in XWiki 15.0-rc-1, 14.10.4, and 14.4.8. The easiest possible workaround is to edit file `<xwiki app>/templates/importinline.vm` and apply the modification described in commit 28905f7f518cc6f21ea61fe37e9e1ed97ef36f01.