CVE-2026-46353

High

Description

BigBlueButton is an open-source virtual classroom. Prior to 3.0.21, bbb-web checksum validation could be bypassed when a presentationUploadExternalUrl parameter was supplied to API request handling in CreateMeeting.java and ValidationService.java, allowing a user to send valid requests to some endpoints without a checksum. This issue is fixed in version 3.0.21.

SeverityHigh
CVSS8.1
Exploit probability—
ProductBigbluebutton
PublishedJul 16, 2026
First seenJul 16, 2026

How to fix

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

Affected products

ProductAffected versionsFixed in
bigbluebutton bigbluebutton< 3.0.21—

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CVE-2026-46353 · Bigbluebutton · Dark Radar