CVE-2026-46351CWE-330

BigBlueButton: Insecure Randomness allows to guess user's conference session token and impersonate them

High · published July 16, 2026

CVSS v3.1
8.1
EPSS
0%
Percentile
39.1
In the wild
Unconfirmed
What it is

BigBlueButton is an open-source virtual classroom. Prior to 3.0.21, bbb-web generated conference sessionToken values with insufficiently secure randomness in bbb-common-web/src/main/java/org/bigbluebutton/api/Util.java and bigbluebutton-web/grails-app/controllers/org/bigbluebutton/web/controllers/ApiController.groovy, allowing a session user to predict other users' conference session tokens and impersonate them. This issue is fixed in version 3.0.21.

The record
Technical detail
CVSS v3.1
8.1 · HIGH
Vector
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:N
CVSS v4.0
Not supplied
EPSS
0.00462 · 39.1th percentile
Weakness
CWE-330 · Use of Insufficiently Random Values
Published
2026-07-16T17:58Z
EPSS history
Timeline
  • 16 JUL 17:58Z
    BigBlueButton: Insecure Randomness allows to guess user's conference session token and impersonate them
    cvelistv5