CVE-2026-55491
BigBlueButton: Stored XSS in Screenshare Recording Playback via Unescaped Meeting Name
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.
No summary for this CVE yet.
CVSS Vector Breakdown
Exploitability
AV:NAttack VectorNetwork
AC:LAttack ComplexityLow
PR:LPrivileges RequiredLow
UI:RUser InteractionRequired
Scope
S:CScopeChanged
Impact
C:LConfidentialityLow
I:LIntegrityLow
A:NAvailabilityNone
Weaknesses
Affected Products
bigbluebutton
oss-projectaka bbb
Exploitability
No known exploits, KEV entries, or remediation guidance available for this vulnerability yet.
Attack Graph
Products CVE Techniques Tactics
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MITRE ATT&CK
2 techniques Execution
Initial Access
References
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