Loco Translate < 2.6.1 - Authenticated Stored Cross-Site Scripting

The Loco Translate WordPress plugin before 2.6.1 does not properly remove inline events from elements in the source translation strings before outputting them in the editor in the plugin admin panel, allowing any user with access to the plugin (Translator and Administrator by default) to add arbitrary javascript payloads to the source strings leading to a stored cross-site scripting (XSS) vulnerability.