CVE-2026-46355

High

Description

BigBlueButton is an open-source virtual classroom. Prior to 3.0.23, BigBlueButton exposed /bigbluebutton/api/handleJoinExistingUser through bigbluebutton-web/grails-app/controllers/org/bigbluebutton/web/controllers/ApiController.groovy. A requester able to supply an existingUserID for an active participant could reuse that participant's session and impersonate the participant in the same meeting because handleJoinExistingUser was a routable controller action rather than a private helper. This issue is fixed in version 3.0.23.

SeverityHigh
CVSS7.1
Exploit probability—
ProductBigbluebutton
PublishedAug 20, 2026
First seenAug 20, 2026

How to fix

Sources list no fixed version or patch link for this vulnerability.

Affected products

ProductAffected versionsFixed in
bigbluebutton bigbluebutton< 3.0.23—

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CVE-2026-46355 · Bigbluebutton · Dark Radar