Improper Authentication in BigBlueButton - CVE-2026-46355
Published: June 4, 2026
Vulnerability identifier: #VU133355
CSH Severity: Medium
CVSS v4.0: CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:L/VI:H/VA:N/SC:N/SI:N/SA:N/E:U/U:Green
CVE-ID: CVE-2026-46355
CWE-ID: CWE-287
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 attacker to bypass authentication process.
The vulnerability exists due to an error in when processing authentication requests in /bigbluebutton/api/handleJoinExistingUser. A remote user can impersonate other existing users in the same session.
How to mitigate CVE-2026-46355
Install updates from vendor's website.