CVE-2026-27737
Description
BigBlueButton is an open-source virtual classroom. In versions prior to 3.0.19, the recording playback (presentation format) was not sanitizing user's input in public chat. This allowed for a malicious actor to craft and carry out a targeted XSS attack, activated on anyone replaying the recording. This issue has been fixed 3.0.19.
Predictions
Heuristic predictions, AS-IS, for prioritization only.
Mitigations
No mitigations published for this CVE yet.
The vendor-content worker queues fetches as references arrive (check back in a few minutes). Or — if you've already worked around this in production — publish your fix to the community-verified tier.
✚ Propose a mitigation on Community → Mitigations published via the community go through AI scoring + 2 human reviewers + 7-day silent objection window before landing here withsource_tier=community-verified.
References
- https://github.com/bigbluebutton/bbb-playback/commit/09e89bfe4ff8488b68c3ff040d3081e419dc89b1
- https://github.com/bigbluebutton/bigbluebutton/commit/69f45aa1b963dc7d80179d0155acc670aec5c4fc
- https://github.com/bigbluebutton/bigbluebutton/releases/tag/v3.0.19
- https://github.com/bigbluebutton/bigbluebutton/security/advisories/GHSA-8vv7-vj94-q2pv
- https://github.com/blindsidenetworks/scalelite/releases/tag/v1.7.0
CWEs
CWE-79
Community-verified mitigations for this CVE will appear above when contributors publish them.
Verify integrity in audit chain (admin only). AS-IS.