Description
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.
Scores
CVSS v3
2.0
EPSS
0.0004
EPSS Percentile
10.6%
Attack Vector
NETWORK
CVSS:3.1/AV:N/AC:H/PR:H/UI:R/S:U/C:L/I:N/A:N
CISA SSVC
Vulnrichment
Exploitation
none
Automatable
no
Technical Impact
partial
Details
CWE
CWE-200
Status
published
Products (1)
bigbluebutton/bigbluebutton
< 3.0.20
Published
Feb 21, 2026
Tracked Since
Feb 21, 2026