CVE-2026-55489 json
BigBlueButton: IDOR on BBB through /api/graphql via POST parameter "presentationId" leads to Authentication Bypass
published 2026-08-20 2 mo ago modified 2026-10-26 13 d ago also EUVD-2026-63683
- cvss
- 4.9
- version 3.1, CNA
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 0.3%
- EPSS 0.3% chance of exploitation in 30 days, percentile 24%
- public exploits
- 0
- none known
Summary
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.
Patch / fix
CISA SSVC
- Exploitation
- none
- Automatable
- no
- Technical impact
- partial
- Assessed
- 2 mo ago
Exploit prediction
0.31% chance of exploitation in the next 30 days, higher than 24% of all scored CVEs (FIRST EPSS, 2026-11-08).
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| CNA | 3.1 | 4.9 | CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:C/C:N/I:L/A:L |
Affected products
- bigbluebutton bigbluebutton
Classification
- Weakness
-
- CWE-639 Authorization Bypass Through User-Controlled Key
References
Sources
- CVE List CVE-2026-55489
- NVD CVE-2026-55489
Fencer Vulns keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.