CVE-2026-55491: medium-severity vulnerability in bigbluebutton
BigBlueButton: Stored XSS in Screenshare Recording Playback via Unescaped Meeting Name
Published · Updated
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13Vexday Risk Score
No sign of exploitation. No public exploitation artifact known so far.
ssvc Trackcvss 5.4epss 0.3%
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.
CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N
Affected products
bigbluebutton · bigbluebuttonRelated CVEs — bigbluebutton
In the same product, most dangerous first.
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