Auth bypass in Bigbluebutton

CVE-2026-41127

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.

Vulnerability class: IDOR (Insecure Direct Object Reference)

Published · last modified .

CVSS v3 metric

CVSS v3 base score 6.5 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:N.

EPSS exploit prediction

EPSS: 0.003 (20.3th percentile), scored .

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 20th percentile — 20.3% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS trend (30 days)EPSS over the last 30 days for CVE-2026-41127: held from 0.002 to 0.003.

EPSS over last 30 days · oldest: 0.002 · newest: 0.003 · change: +0.001

Affected products

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2026-41127?
CVE-2026-41127 is a medium-severity vulnerability in Bigbluebutton, classified under Authorization Bypass Through User-Controlled Key. CVSS score: 6.5/10. Published 2026-04-22.
How severe is CVE-2026-41127?
Medium severity. CVSS v3 base score is 6.5 out of 10.