CVE-2026-55491
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.
Published:Aug 20, 2026
Last Modified:Aug 21, 2026
EPS:Aug 20, 2026
EPSS Score:0.00165
CVSS Score:5.4
Affected Products
Vendor
Product
Action
Vendor
Bigbluebutton
Product
Bigbluebutton
Bigbluebutton
Bigbluebutton
Exploits
No exploit reference
Common Weakness Enumeration
Common Attack Pattern Enumeration and Classification (CAPEC)
Related CVEs
Common Vulnerability Scoring System
Attack Vector
Network
Adjacent
Local
Physical
Privileges Required
None
Low
High
User Interaction
None
Required
Scope
Unchanged
Changed
Confidentiality
None
Low
High
Integrity
None
Low
High
Availability
None
Low
High
