{"items":[{"id":"NVI-00014129","kind":"vulnerability","title":"Opencast: Stored XSS in Paella player via WebVTT/DFXP caption cue text","revision":1,"unknowns":["Customer inventory, deployment, reachability and exploitation have not been inspected."],"lifecycle":"active","identifiers":["GHSA-m6c8-jcw2-5r25","CVE-2026-77615"],"plain_summary":"GitHub lists this reviewed advisory for org.opencastproject:opencast-engage-paella-player-7, org.opencastproject:opencast-engage-paella-player-7, paella-core. Published version ranges and source prerequisites are shown below; this is not an inspection of a visitor’s application.","review_status":"source_listed","control_topics":[],"public_actions":[{"summary":"Identify the exact component and deployed version, examine the linked publisher’s conditions, and retain evidence of any mitigation.","source_ids":["sr-4d4676fc870dcca3da6e4c315b2ac4cc"],"action_type":"investigate","limitations":"Confirm current vendor support, compatibility and deployment evidence. This report has not tested a fix in your system.","current_supported_target":null}],"schema_version":"1.1.0","source_metrics":[{"kind":"CVSS","as_of":"2026-09-18T13:12:03.000Z","value":"8.7 high","meaning":"GitHub source severity; exploitability and local consequence require separate evidence.","source_id":"sr-4d4676fc870dcca3da6e4c315b2ac4cc"}],"why_it_matters":"Published affected context helps an owner decide what evidence to gather. This report has not examined your application.","related_sources":[{"id":"sr-4d4676fc870dcca3da6e4c315b2ac4cc","url":"https://github.com/advisories/GHSA-m6c8-jcw2-5r25","basis":"vendor_advisory","notes":"GitHub Advisory Database; CC-BY-4.0. Each advisory links its original attribution. Null normalizes fields.","title":"GHSA-m6c8-jcw2-5r25","publisher":"GitHub Advisory Database","observed_at":"2026-11-01T14:29:49.409Z"}],"affected_context":[{"certainty":"source_listed","source_ids":["sr-4d4676fc870dcca3da6e4c315b2ac4cc"],"technology":"org.opencastproject:opencast-engage-paella-player-7","known_exclusions":[],"conditions_summary":"## Summary\n\nThe 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 Opencast origin.\n\nThe caption track is read from any media package element with a `captions/*` flavor and is served, with the player manifest, to anonymous viewers through `/search/episode.json`. The caption plugins that consume it are enabled in the default player configuration, the \"Subtitles\" upload that produces a `captions/source` track is active by default, and no caption processing step escapes the cue text.\n\nA user who can upload a subtitle to an event and publish it stores the payload in the published caption file. Any viewer who opens the event and turns captions on runs the script.\n\nResult: a non-admin content author stores JavaScript in a subtitle cue that executes in the browser session of every viewer who enables captions on that event, including anonymous viewers and authenticated staff.\n\n## Affected\n\nopencast/opencast, `engage-paella-player` module. Supported relea","public_affected_ranges":["< 19.7"]},{"certainty":"source_listed","source_ids":["sr-4d4676fc870dcca3da6e4c315b2ac4cc"],"technology":"org.opencastproject:opencast-engage-paella-player-7","known_exclusions":[],"conditions_summary":"## Summary\n\nThe 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 Opencast origin.\n\nThe caption track is read from any media package element with a `captions/*` flavor and is served, with the player manifest, to anonymous viewers through `/search/episode.json`. The caption plugins that consume it are enabled in the default player configuration, the \"Subtitles\" upload that produces a `captions/source` track is active by default, and no caption processing step escapes the cue text.\n\nA user who can upload a subtitle to an event and publish it stores the payload in the published caption file. Any viewer who opens the event and turns captions on runs the script.\n\nResult: a non-admin content author stores JavaScript in a subtitle cue that executes in the browser session of every viewer who enables captions on that event, including anonymous viewers and authenticated staff.\n\n## Affected\n\nopencast/opencast, `engage-paella-player` module. Supported relea","public_affected_ranges":[">= 20.0, < 20.2"]},{"certainty":"source_listed","source_ids":["sr-4d4676fc870dcca3da6e4c315b2ac4cc"],"technology":"paella-core","known_exclusions":[],"conditions_summary":"## Summary\n\nThe 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 Opencast origin.\n\nThe caption track is read from any media package element with a `captions/*` flavor and is served, with the player manifest, to anonymous viewers through `/search/episode.json`. The caption plugins that consume it are enabled in the default player configuration, the \"Subtitles\" upload that produces a `captions/source` track is active by default, and no caption processing step escapes the cue text.\n\nA user who can upload a subtitle to an event and publish it stores the payload in the published caption file. Any viewer who opens the event and turns captions on runs the script.\n\nResult: a non-admin content author stores JavaScript in a subtitle cue that executes in the browser session of every viewer who enables captions on that event, including anonymous viewers and authenticated staff.\n\n## Affected\n\nopencast/opencast, `engage-paella-player` module. Supported relea","public_affected_ranges":["< 1.50.6"]}],"null_published_at":"2026-11-02T10:00:37.211Z","source_updated_at":"2026-09-18T13:12:03.000Z","source_disclosed_at":"2026-09-18T13:11:59.000Z","is_synthetic_fixture":false,"null_last_reviewed_at":null,"public_change_summary":"First indexed by Null; source disclosure date is shown separately.","null_first_observed_at":"2026-11-01T14:29:49.409Z"}],"next_cursor":null,"snapshot_revision":"42594"}