HTML injection in Zoom Linux client

In the Zoom Client for Meetings for Ubuntu Linux before version 5.1.0, there is an HTML injection flaw when sending a remote control request to a user in the process of in-meeting screen sharing. This could allow meeting participants to be targeted for social engineering attacks.

Pre-auth Null pointer crash in on-premise web console

The login routine of the web console in the Zoom On-Premise Meeting Connector before version 4.6.239.20200613, Zoom On-Premise Meeting Connector MMR before version 4.6.239.20200613, Zoom On-Premise Recording Connector before version 3.8.42.20200905, Zoom On-Premise Virtual Room Connector before version 4.4.6344.20200612, and Zoom On-Premise Virtual Room Connector Load Balancer before version 2.5.5492.20200616 fails to validate that a NULL byte was sent while authenticating. This could lead to a crash of the login service.

Authenticated remote command execution with root privileges via web console in MMR

The network proxy page on the web portal for the Zoom On-Premise Meeting Connector Controller before version 4.6.365.20210703, Zoom On-Premise Meeting Connector MMR before version 4.6.365.20210703, Zoom On-Premise Recording Connector before version 3.8.45.20210703, Zoom On-Premise Virtual Room Connector before version 4.4.6868.20210703, and Zoom On-Premise Virtual Room Connector Load Balancer before version 2.5.5496.20210703 fails to validate input sent in requests to set the network proxy password. This could lead to remote command injection by a web portal administrator.

All versions of the Zoom Plugin for Microsoft Outlook for MacOS before 5.3.52553.0918 contain a Time-of-check Time-of-use (TOC/TOU) vulnerability during the plugin installation process. This could allow a standard user to write their own malicious application to the plugin directory, allowing the malicious application to execute in a privileged context.

A user-writable application bundle unpacked during the install for all versions of the Zoom Plugin for Microsoft Outlook for Mac before 5.0.25611.0521 allows for privilege escalation to root.

Zoom through 5.5.4 sometimes allows attackers to read private information on a participant's screen, even though the participant never attempted to share the private part of their screen. When a user shares a specific application window via the Share Screen functionality, other meeting participants can briefly see contents of other application windows that were explicitly not shared. The contents of these other windows can (for instance) be seen for a short period of time when they overlay the shared window and get into focus. (An attacker can, of course, use a separate screen-recorder application, unsupported by Zoom, to save all such contents for later replays and analysis.) Depending on the unintentionally shared data, this short exposure of screen contents may be a more or less severe security issue.

An exploitable partial path traversal vulnerability exists in the way Zoom Client version 4.6.10 processes messages including shared code snippets. A specially crafted chat message can cause an arbitrary binary planting which could be abused to achieve arbitrary code execution. An attacker needs to send a specially crafted message to a target user or a group to trigger this vulnerability. For the most severe effect, target user interaction is required.

An exploitable path traversal vulnerability exists in the Zoom client, version 4.6.10 processes messages including animated GIFs. A specially crafted chat message can cause an arbitrary file write, which could potentially be abused to achieve arbitrary code execution. An attacker needs to send a specially crafted message to a target user or a group to exploit this vulnerability.

The Zoom Client before 4.4.53932.0709 on macOS allows remote code execution, a different vulnerability than CVE-2019-13450. If the ZoomOpener daemon (aka the hidden web server) is running, but the Zoom Client is not installed or can't be opened, an attacker can remotely execute code with a maliciously crafted launch URL. NOTE: ZoomOpener is removed by the Apple Malware Removal Tool (MRT) if this tool is enabled and has the 2019-07-10 MRTConfigData.

In the Zoom Client through 4.4.4 and RingCentral 7.0.136380.0312 on macOS, remote attackers can force a user to join a video call with the video camera active. This occurs because any web site can interact with the Zoom web server on localhost port 19421 or 19424. NOTE: a machine remains vulnerable if the Zoom Client was installed in the past and then uninstalled. Blocking exploitation requires additional steps, such as the ZDisableVideo preference and/or killing the web server, deleting the ~/.zoomus directory, and creating a ~/.zoomus plain file.

In the Zoom Client before 4.4.2 on macOS, remote attackers can cause a denial of service (continual focus grabs) via a sequence of invalid launch?action=join&confno= requests to localhost port 19421.

Zoom clients on Windows (before version 4.1.34814.1119), Mac OS (before version 4.1.34801.1116), and Linux (2.4.129780.0915 and below) are vulnerable to unauthorized message processing. A remote unauthenticated attacker can spoof UDP messages from a meeting attendee or Zoom server in order to invoke functionality in the target client. This allows the attacker to remove attendees from meetings, spoof messages from users, or hijack shared screens.