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CVE-2026-46353highCWE-284

BigBlueButton API checksum bypass via presentationUploadExternalUrl

21Vexday Risk Score

No sign of exploitation. No public exploitation artifact known so far.

ssvc Trackcvss 8.1epss 0.3%
exploitation probability
0.3%top 82% of all CVEs
observed exploitation
nono source reports it
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.
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:N