CVE-2026-55489
BigBlueButton: IDOR on BBB through /api/graphql via POST parameter "presentationId" leads to Authentication Bypass
CVSS Score
4.9
EPSS Score
0.0%
EPSS Percentile
0th
BigBlueButton is an open-source virtual classroom. Prior to 3.0.29, BigBlueButton presenters could submit a presentationId through /api/graphql that identified a presentation belonging to another meeting. akka-bbb-apps/src/main/scala/org/bigbluebutton/core/apps/presentationpod/RemovePresentationPubMsgHdlr.scala did not verify the presentation's meeting identifier before deletion, allowing a presenter who knew the identifier to delete another meeting's presentation and disrupt its availability. This issue is fixed in version 3.0.29.
| CWE | CWE-639 |
| Vendor | bigbluebutton |
| Product | bigbluebutton |
| Published | Aug 20, 2026 |
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CVSS v3 Breakdown
CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:C/C:N/I:L/A:L Attack Vector
Network
Attack Complexity
High
Privileges Required
Low
User Interaction
None
Scope
Changed
Confidentiality
None
Integrity
Low
Availability
Low
Affected Versions
bigbluebutton / bigbluebutton
< 3.0.29