BigBlueButton is an open-source virtual classroom. Versions prior to 3.0.24 have a missing authorization that allows viewers to inject/overwrite captions Version 3.0.24 tightened the permissions on who is able to submit captions. No known workarounds are available.
Exploitability
AV:NAC:LPR:LUI:NScope
S:UImpact
C:NI:HA:N6.5/CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:NOther