CVE-2026-27467

BigBlueButton is an open-source virtual classroom. In versions 3.0.19 and below, when first joining a session with the microphone muted, the client sends audio to the server regardless of mute state. Media is discarded at the server side, so it isn't audible to any participants, but this may allow for malicious server operators to access audio data. The behavior is only incorrect between joining the meeting and the first time the user unmutes. This issue has been fixed in version 3.0.20.

CVSS v3 2.0 LOW

2.0^/10

CVSS v3 : LOW

Vector :

Exploitability : 0.5 / Impact : 1.4

Attack Vector NETWORK

Attack Complexity HIGH

Privileges Required HIGH

User Interaction REQUIRED

Confidentiality Impact LOW

Integrity Impact NONE

Availability Impact NONE

Scope UNCHANGED

References

Link	Resource
https://github.com/bigbluebutton/bigbluebutton/commit/3aa47832bc2b17178799bd932453c226e8f95703	Patch
https://github.com/bigbluebutton/bigbluebutton/security/advisories/GHSA-6gj9-5rhm-68j8	Patch Vendor Advisory

Configurations

Configuration 1 (hide)

cpe:2.3:a:bigbluebutton:bigbluebutton:*:*:*:*:*:*:*:*

History

No history.

Information

Published : 2026-02-21 08:16

Updated : 2026-02-26 18:54

NVD link : CVE-2026-27467

Mitre link : CVE-2026-27467

CVE.ORG link : CVE-2026-27467

JSON object : View

Products Affected

bigbluebutton

bigbluebutton

CWE

CWE-200

Exposure of Sensitive Information to an Unauthorized Actor

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