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.

BigBlueButton is an open-source virtual classroom. Prior to 3.0.29, BigBlueButton presenters could submit a presentationId through /api/graphql that identified a presentation belonging to another meeting. akka-bbb-apps/src/main/scala/org/bigbluebutton/core/apps/presentationpod/RemovePresentationPubMsgHdlr.scala did not verify the presentation's meeting identifier before deletion, allowing a presenter who knew the identifier to delete another meeting's presentation and disrupt its availability. This issue is fixed in version 3.0.29.

BigBlueButton is an open-source virtual classroom. Prior to 3.0.23, BigBlueButton exposed /bigbluebutton/api/handleJoinExistingUser through bigbluebutton-web/grails-app/controllers/org/bigbluebutton/web/controllers/ApiController.groovy. A requester able to supply an existingUserID for an active participant could reuse that participant's session and impersonate the participant in the same meeting because handleJoinExistingUser was a routable controller action rather than a private helper. This issue is fixed in version 3.0.23.

BigBlueButton is an open-source virtual classroom. Prior to 3.0.23, BigBlueButton allowed authenticated moderators to inject SQL through the meetingId and userId values used by refreshBreakoutRoomsVisibleForUsers in akka-bbb-apps/src/main/scala/org/bigbluebutton/core/db/BreakoutRoomUserDAO.scala. The method interpolated those values into breakout room visibility queries, allowing arbitrary SQL execution against the application database. This issue is fixed in version 3.0.23.

BigBlueButton is an open-source virtual classroom. In versions prior to 3.0.19, the recording playback (presentation format) was not sanitizing user's input in public chat. This allowed for a malicious actor to craft and carry out a targeted XSS attack, activated on anyone replaying the recording. This issue has been fixed 3.0.19.

BigBlueButton is an open-source virtual classroom. Prior to 3.0.23, the presentation URL validation did not properly restrict access to site local and link local addresses. The redirect following logic now pins resolved IPs. This issue is fixed in version 3.0.23.

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.

BigBlueButton is an open-source virtual classroom. Prior to 3.0.21, bbb-web checksum validation could be bypassed when a presentationUploadExternalUrl parameter was supplied to API request handling in CreateMeeting.java and ValidationService.java, allowing a user to send valid requests to some endpoints without a checksum. This issue is fixed in version 3.0.21.

BigBlueButton is an open source virtual classroom designed to help teachers teach and learners learn. In affected versions are affected by a Server-Side Request Forgery (SSRF) vulnerability. In an insertDocument API request the user is able to supply a URL from which the presentation should be downloaded. This URL was being used without having been successfully validated first. An update to the followRedirect method in the PresentationUrlDownloadService has been made to validate all URLs to be used for presentation download. Two new properties presentationDownloadSupportedProtocols and presentationDownloadBlockedHosts have also been added to bigbluebutton.properties to allow administrators to define what protocols a URL must use and to explicitly define hosts that a presentation cannot be downloaded from. All URLs passed to insertDocument must conform to the requirements of the two previously mentioned properties. Additionally, these URLs must resolve to valid addresses, and these addresses must not be local or loopback addresses. There are no workarounds. Users are advised to upgrade to a patched version of BigBlueButton.

BigBlueButton is an open-source virtual classroom. Versions prior to 3.0.24 have an Open Redirect through bigbluebutton/api/join via get-parameter "logoutURL." Version 3.0.24 has adjusted the handling of requests with incorrect checksum so that the default logoutURL is used. No known workarounds are available.

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.

The BigBlueButton plugin for WordPress is vulnerable to Stored Cross-Site Scripting via the the moderator code and viewer code fields in versions up to, and including, 3.0.0-beta.4 due to insufficient input sanitization and output escaping. This makes it possible for authenticated attackers with author privileges or higher to inject arbitrary web scripts in pages that execute if they can successfully trick a user into performing an action such as clicking on a link.

BigBlueButton is an open-source virtual classroom. In versions on the 3.x branch prior to 3.0.20, the string received with errorRedirectUrl lacks validation, using it directly in the respondWithRedirect function leads to an Open Redirect vulnerability. BigBlueButton 3.0.20 patches the issue. No known workarounds are available.

BigBlueButton is an open-source virtual classroom. In versions 3.0.21 and below, the official documentation for "Server Customization" on Support for ClamAV as presentation file scanner contains instructions that leave a BBB server vulnerable for Denial of Service. The flawed command exposes both ports (3310 and 7357) to the internet. A remote attacker can use this to send complex or large documents to clamd and waste server resources, or shutdown the clamd process. The clamd documentation explicitly warns about exposing this port. Enabling ufw (ubuntu firewall) during install does not help, because Docker routes container traffic through the nat table, which is not managed or restricted by ufw. Rules installed by ufw in the filter table have no effect on docker traffic. In addition, the provided example also mounts /var/bigbluebutton with write permissions into the container, which should not be required. Future vulnerabilities in clamd may allow attackers to manipulate files in that folder. Users are unaffected unless they have opted in to follow the extra instructions from BigBlueButton's documentation. This issue has been fixed in version 3.0.22.

BigBlueButton is an open-source virtual classroom. In versions 3.0.19 and below, when first joining a session with the microphone muted, the client sends audio to the server regardless of mute state. Media is discarded at the server side, so it isn't audible to any participants, but this may allow for malicious server operators to access audio data. The behavior is only incorrect between joining the meeting and the first time the user unmutes. This issue has been fixed in version 3.0.20.

BigBlueButton is an open-source virtual classroom. A denial-of-service (DoS) vulnerability in versions prior to 3.0.13 allows any authenticated user to crash the chat functionality for all participants in a meeting by sending a malformed reactionEmojiId in the GraphQL mutation chatSendMessageReaction. Version 3.0.13 contains a patch. No known workarounds are available.

BigBlueButton is an open-source virtual classroom. A Denial of Service (DoS) vulnerability in versions prior to 3.0.13 allows any authenticated user to freeze or crash the entire server by abusing the polling feature's Choices response type. By submitting a malicious payload with a massive array in the answerIds field, the attacker can cause the current meeting — and potentially all meetings on the server — to become unresponsive. Version 3.0.13 contains a patch. No known workarounds are available.

BigBlueButton is an open-source virtual classroom. In versions prior to 3.0.13, the "Shared Notes" feature contains a Stored Cross-Site Scripting (XSS) vulnerability with the input location being the "Username" field and the output location on the "Shared Notes" page, when a user with a malicious username is editing content. This vulnerability allows a low-privileged user to execute arbitrary JavaScript in the context of higher-privileged users (e.g., Admins) who open the Shared Notes page. Version 3.0.13 fixes the issue.

Greenlight is an end-user interface for BigBlueButton servers. Versions prior to 2.13.0 have an open redirect vulnerability in the Login page due to unchecked the value of the returnto cookie. Versions 2.13.0 contains a patch for the issue.

Greenlight is an end-user interface for BigBlueButton servers. Versions prior to 2.13.0 have an open redirect vulnerability in the Login page due to unchecked the value of the returnto cookie. Versions 2.13.0 contains a patch for the issue.

BigBlueButton is an open source web conferencing system. Versions starting with 2.2 and prior to 2.3.19, 2.4.7, and 2.5.0-beta.2 are vulnerable to regular expression denial of service (ReDoS) attacks. By using specific a RegularExpression, an attacker can cause denial of service for the bbb-html5 service. The useragent library performs checking of device by parsing the input of User-Agent header and lets it go through lookupUserAgent() (alias of useragent.lookup() ). This function handles input by regexing and attackers can abuse that by providing some ReDos payload using SmartWatch. The maintainers removed htmlclient/useragent from versions 2.3.19, 2.4.7, and 2.5.0-beta.2. As a workaround, disable NginX forwarding the requests to the handler according to the directions in the GitHub Security Advisory.

BigBlueButton is an open source web conferencing system. Starting with version 2.2 and prior to versions 2.3.9 and 2.4-beta-1, an attacker can circumvent access controls to obtain the content of public chat messages from different meetings on the server. The attacker must be a participant in a meeting on the server. BigBlueButton versions 2.3.9 and 2.4-beta-1 contain a patch for this issue. There are currently no known workarounds.

BigBlueButton is an open source web conferencing system. In BigBlueButton starting with 2.2 but before 2.3.18 and 2.4-rc-1, an attacker can circumvent access controls to gain access to all breakout rooms of the meeting they are in. The permission checks rely on knowledge of internal ids rather than on verification of the role of the user. Versions 2.3.18 and 2.4-rc-1 contain a patch for this issue. There are currently no known workarounds.

BigBlueButton is an open source web conferencing system. Starting in version 2.2 and prior to versions 2.3.18 and 2.4.1, an attacker could send messages to a locked chat within a grace period of 5s any lock setting in the meeting was changed. The attacker needs to be a participant in the meeting. Versions 2.3.18 and 2.4.1 contain a patch for this issue. There are currently no known workarounds.

Greenlight is a simple front-end interface for your BigBlueButton server. In affected versions an attacker can view any room's settings even though they are not authorized to do so. Only the room owner and administrator should be able to view a room's settings. This issue has been patched in release version 2.12.6.

BigBlueButton is an open source web conferencing system. In affected versions an attacker can embed malicious JS in their username and have it executed on the victim's client. When a user receives a private chat from the attacker (whose username contains malicious JavaScript), the script gets executed. Additionally when the victim receives a notification that the attacker has left the session. This issue has been patched in version 2.4.8 and 2.5.0. There are no known workarounds for this issue.

BigBlueButton is an open source web conferencing system. Users in meetings with private chat enabled are vulnerable to a cross site scripting attack in affected versions. The attack occurs when the attacker (with xss in the name) starts a chat. in the victim's client the JavaScript will be executed. This issue has been addressed in version 2.4.8 and 2.5.0. There are no known workarounds for this issue.

BigBlueButton is an open source web conferencing system. Versions prior to 2.4.3, are subject to Insufficient Verification of Data Authenticity, resulting in Denial of Service. An attacker can make a Meteor call to validateAuthToken using a victim's userId, meetingId, and an invalid authToken. This forces the victim to leave the conference, because the resulting verification failure is also observed and handled by the victim's client. The attacker must be a participant in any meeting on the server. This issue is patched in version 2.4.3. There are no workarounds.

BigBlueButton is an open source web conferencing system. Versions prior to 2.4-rc-6 are subject to Ineffective user bans. The attacker could register multiple users, and join the meeting with one of them. When that user is banned, they could still join the meeting with the remaining registered users from the same extId. This issue has been fixed by improving permissions such that banning a user removes all users related to their extId, including registered users that have not joined the meeting. This issue is patched in versions 2.4-rc-6 and 2.5-alpha-1. There are no workarounds.

BigBlueButton is an open source web conferencing system. Versions prior to 2.4-rc-6, and 2.5-alpha-1 contain Incorrect Authorization for setting emoji status. A user with moderator rights can use the clear status feature to set any emoji status for other users. Moderators should only be able to set none as the status of other users. This issue is patched in 2.4-rc-6 and 2.5-alpha-1There are no workarounds.