CVE-2026-55491EPSS p19.5%
CVE-2026-55491CVE-2026-55491
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.
Scoring
| CVSS | 5.4 () |
| Vector | CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N |
| EPSS | 0.29% probability of exploitation · percentile 19.5% · 2026-10-05T12:00:23Z |
| Last modified | 2026-09-16 |