Medium severity · published Apr 21, 2026
CVE-2026-41126
BigBlueButton has Open Redirect through bigbluebutton/api/join via get-parameter "logoutURL"
4.3
CVSS
0.2%
EPSS
No
On KEV
Description
BigBlueButton is an open-source virtual classroom. Versions prior to 3.0.24 have an Open Redirect through bigbluebutton/api/join via get-parameter "logoutURL." Version 3.0.24 has adjusted the handling of requests with incorrect checksum so that the default logoutURL is used. No known workarounds are available.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:N/A:N
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
Required
Confidentiality
Low
Integrity
None
Availability
None
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.2% · higher than 14% 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-2026-41126
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-41126
github.com
https://github.com/bigbluebutton/bigbluebutton/security/advisories/GHSA-cvwj-4pcp-f3g8
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