Improper Handling of Extra Parameters in BigBlueButton - #VU150171
Published: September 16, 2026
Vulnerability identifier: #VU150171
CSH Severity: Medium
CVSS v4: 7.2 [CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:L/VI:H/VA:L/SC:N/SI:N/SA:N]
CVE-ID: N/A
CWE-ID: CWE-235
Exploitation vector: Remote access
Exploit availability:
No public exploit available
Vulnerability details
The vulnerability allows a remote attacker to gain unauthorized access to otherwise restricted functionality.
The vulnerability exists due to insufficient validation and encoding of parameter names when generating signed join URLs. A remote user can inject parameters or duplicate the "checksum" parameter and modify the URL behavior.
Affected software
BigBlueButton
Remediation
Install updates from vendor's website.
BigBlueButton - addressed in versions 3.0.37, 4.0.0 rc.2