Medium severity · published Jul 16, 2026
CVE-2026-46404
BigBlueButton: Presentation URL Security Hardening
6.8
CVSS
0.4%
EPSS
No
On KEV
Description
BigBlueButton is an open-source virtual classroom. Prior to 3.0.23, the presentation URL validation did not properly restrict access to site local and link local addresses. The redirect following logic now pins resolved IPs. This issue is fixed in version 3.0.23.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:C/C:H/I:N/A:N
Attack vector
Network
Complexity
Low
Privileges
High
User interaction
None
Confidentiality
High
Integrity
None
Availability
None
Scope
Changed
Exploitation
Is it being used?
Exploit prediction (EPSS)0.4% · higher than 38% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
BI
bigbluebutton · bigbluebutton
< 3.0.23 · source: vendor
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-46404
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-46404
github.com
https://github.com/bigbluebutton/bigbluebutton/commit/7ccc60c965d744d9fb637715052352a1e59a2c27
github.com
https://github.com/bigbluebutton/bigbluebutton/security/advisories/GHSA-xqm3-6q7q-4v5h
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