Authorization bypass through user-controlled key in BigBlueButton - #VU125912
Published: April 14, 2026
Vulnerability identifier: #VU125912
CSH Severity: Low
CVSS v4.0: CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:H/VA:N/SC:N/SI:N/SA:N/E:U/U:Clear
CVE-ID: N/A
CWE-ID: CWE-639
Exploitation vector: Remote access
Exploit availability:
No public exploit available
Vendor: Blindside Networks
Affected software:
BigBlueButton
BigBlueButton
Detailed vulnerability description
The vulnerability allows a remote user to modify captions.
The vulnerability exists due to improper access control in caption submission handling in bbb-apps-akka and bbb-graphql-actions when handling caption submission requests. A remote user can submit captions or overwrite existing ones to modify captions.
Viewers and non-audio users are able to perform the unauthorized caption changes.
Remediation
Install security update from vendor's website.