Medium severity · published Apr 21, 2026
CVE-2026-41127
BigBlueButton's missing authorization allows viewer to inject/overwrite captions
6.5
CVSS
0.2%
EPSS
No
On KEV
Description
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.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:N
Attack vector
Network
Complexity
Low
Privileges
Low
User interaction
None
Confidentiality
None
Integrity
High
Availability
None
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.2% · higher than 7% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
BI
bigbluebutton · bigbluebutton
< 3.0.24 · source: vendor
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-41127
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-41127
github.com
https://github.com/bigbluebutton/bigbluebutton/security/advisories/GHSA-q387-2q28-mg33
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