CVE-2022-29232 is a vulnerability identified in BigBlueButton, an open-source web conferencing platform widely used for online meetings and virtual classrooms. The flaw exists in versions starting from 2.2 up to but not including 2.3.9, and also in versions from 2.4-alpha-1 up to but not including 2.4-beta-1. The vulnerability allows an attacker who is a participant in any meeting hosted on the affected server to bypass access controls and access the content of public chat messages from other meetings on the same server. This means that a malicious participant can view sensitive information shared in chats of meetings they are not authorized to join. The issue is classified under CWE-200, which concerns the exposure of sensitive information to unauthorized actors. The vulnerability does not require the attacker to have administrative privileges but does require them to be a legitimate participant in at least one meeting on the server. The flaw was patched in versions 2.3.9 and 2.4-beta-1. No known workarounds exist, and there are no reports of active exploitation in the wild. The root cause is an access control bypass that fails to properly isolate chat message data between different meetings, leading to cross-meeting data leakage. This can compromise confidentiality of meeting communications and potentially expose sensitive organizational information or personal data shared in chats.

For European organizations, the impact of this vulnerability can be significant, especially for entities relying on BigBlueButton for confidential communications, such as educational institutions, government agencies, and private enterprises. Exposure of chat messages across meetings can lead to leakage of sensitive information including intellectual property, personal data protected under GDPR, strategic discussions, or confidential operational details. This undermines trust in the platform and can result in reputational damage, regulatory penalties, and potential legal liabilities. Since the attacker must be a participant in a meeting, insider threats or unauthorized users gaining meeting access pose a direct risk. The vulnerability affects the confidentiality of communications but does not directly impact system integrity or availability. However, the breach of confidentiality alone can have cascading effects on organizational security posture and compliance obligations.

To mitigate this vulnerability, European organizations should urgently upgrade all BigBlueButton instances to version 2.3.9 or later, or 2.4-beta-1 or later, where the patch is applied. Given the absence of workarounds, patching is the primary defense. Organizations should also enforce strict meeting access controls to limit participation to trusted users only, reducing the risk of malicious insiders or unauthorized participants exploiting the flaw. Implementing multi-factor authentication (MFA) for meeting access can further reduce unauthorized entry. Monitoring and logging participant activities during meetings can help detect suspicious behavior indicative of exploitation attempts. Additionally, organizations should review and limit the sharing of highly sensitive information in public chats until systems are patched. For hosted or managed BigBlueButton services, verify with providers that the platform is updated. Finally, conduct user awareness training to highlight the importance of secure meeting practices and the risks of sharing sensitive information in chats.