CVE-2026-55489
BigBlueButton: IDOR on BBB through /api/graphql via POST parameter "presentationId" leads to Authentication Bypass
CVE-2026-55489 is a medium vulnerability (CVSS 4.9) in Bigbluebutton, published August 20, 2026. No source lists public exploit code. EPSS puts the chance of exploitation in the next 30 days at 0.31%, the 24th percentile. No source names a fixed version.
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.
Attack profile
How easy it is to exploit
- Attack vector
- Network
- Complexity
- High
- Privileges needed
- Low
- User interaction
- None
What an attacker can affect
- Confidentiality
- None
- Integrity
- Low
- Availability
- Low
Exploit likelihood
What each source reports
CVE List Score used
BigBlueButton: IDOR on BBB through /api/graphql via POST parameter "presentationId" leads to Authentication Bypass
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.
- Record
CVE-2026-55489- CVSS 3.1
- 4.9 Medium
CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:C/C:N/I:L/A:L - Weakness
- CWE-639
- Updated
- 2026-11-02
EUVDEUVD-2026-63683
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.
- Record
EUVD-2026-63683- CVSS 3.1
- 4.9 Medium
CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:C/C:N/I:L/A:L - Updated
- 2026-11-02
NVD
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.
- Record
CVE-2026-55489- CVSS 3.1
- 4.9 Medium
CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:C/C:N/I:L/A:L - Weakness
- CWE-639
- Updated
- 2026-11-02
OSV
BigBlueButton: IDOR on BBB through /api/graphql via POST parameter "presentationId" leads to Authentication Bypass
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.
- Record
CVE-2026-55489- CVSS 3.1
- 4.9 Medium
CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:C/C:N/I:L/A:L - Weakness
- CWE-639
- Updated
- 2026-11-02
Affected products
History
| When | Changed | Sources |
|---|---|---|
| 2026-11-02 | created | CVE List, EUVD, NVD, OSV |
References
github.com/bigbluebutton/bigbluebutton/security/advisories/GHSA-jxpq-r3h3-p75g
nvd.nist.gov/vuln/detail/CVE-2026-55489