Opencast: Stored XSS in Paella player via WebVTT/DFXP caption cue text

Summary The Opencast Paella player renders caption cue text into innerHTML without escaping. The captions canvas clears captionsContainer.innerHTML and then appends each active cue with captionsContainer.innerHTML += cue, so HTML inside a WebVTT or DFXP cue becomes live DOM and executes in the...