CVE-2026-55491

Published Aug 20, 2026

Last updated 3 days ago

Overview

Description
BigBlueButton is an open-source virtual classroom. Prior to 3.0.29, BigBlueButton failed to escape meetingName in record-and-playback/screenshare/playback/index.html.erb when generating the screenshare playback format. A low-privileged user could store a crafted meeting name that embedded script content, and the script executed in another user's browser when that user replayed the recording. This issue is fixed in version 3.0.29.
Source
security-advisories@github.com
NVD status
Received

Risk scores

CVSS 3.1

Type
Secondary
Base score
5.4
Impact score
2.7
Exploitability score
2.3
Vector string
CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N
Severity
MEDIUM

Weaknesses

security-advisories@github.com
CWE-79

Social media

Hype score
Not currently trending