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OpenAdvisories
Medium · 5.4 CVE-2026-55491 EUVD-2026-63682

BigBlueButton: Stored XSS in Screenshare Recording Playback via Unescaped Meeting Name

Published Aug 20, 2026 · Updated Aug 21, 2026 · Assigned by GitHub_M

Description

BigBlueButton is an open-source virtual classroom. Prior to 3.0.29, BigBlueButton failed to escape meetingName in record-and-playback/screenshare/playback/index.html.erb when generating the screenshare playback format. A low-privileged user could store a crafted meeting name that embedded script content, and the script executed in another user's browser when that user replayed the recording. This issue is fixed in version 3.0.29.

Affected products

VendorProductAffectedFixed
bigbluebutton bigbluebutton < 3.0.29 —

Advisories 1

References