title: BigBlueButton Stored Cross-site Scripting vulnerability at Guest Lobby
description: BigBlueButton is an open-source virtual classroom. Prior to versions 2.6.11 and 2.7.0-beta.3, Guest Lobby was vulnerable to cross-site scripting when users wait to enter the meeting due to inserting unsanitized messages to the element using unsafe innerHTML. Text sanitizing was added for lobby messages starting in versions 2.6.11 and 2.7.0-beta.3. There are no known workarounds.
problem types: CWE-79: Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')
affected:
{
vendor: bigbluebutton
product: bigbluebutton
versions:
version: < 2.6.11, status: affected
version: >= 2.7.0-alpha.1, < 2.7.0-beta.3, status: affected
}
metrics:
cvssV3_1: [
attackComplexity: LOW
attackVector: NETWORK
availabilityImpact: LOW
baseScore: 6.3
baseSeverity: MEDIUM
confidentialityImpact: LOW
integrityImpact: LOW
privilegesRequired: LOW
scope: UNCHANGED
userInteraction: NONE
vectorString: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:L
version: 3.1
]