Tenable Researcher David Wells discovered a vulnerability in Zoom’s Desktop Conferencing Application that allows an attacker to hijack screen controls, spoof chat messages or kick and lock attendees out of meetings. Zoom has released updates for macOS, Windows and Linux.

Tenable Research Advisory: Zoom Unauthorized Command Execution (CVE-2018-15715)

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.

The version of Zoom Client for Meetings installed on the remote host is prior to 4.1.34460.1105. It is, therefore, affected by a vulnerability as referenced in the ZSB-18001 advisory.

  - A vulnerability in the Zoom client could allow a remote, unauthenticated attacker to control meeting     functionality such as ejecting meeting participants, sending chat messages, and controlling participant     microphone muting. If the attacker was also a valid participant in the meeting and another participant was     sharing their desktop screen, the attacker could also take control of that participant's keyboard and     mouse. The vulnerability is due to the fact that Zoom's internal messaging pump dispatched both client     User Datagram Protocol (UDP) and server Transmission Control Protocol (TCP) messages to the same message     handler. An attacker can exploit this vulnerability to craft and send UDP packets which get interpreted as     messages processed from the trusted TCP channel used by authorized Zoom servers. Zoom released client     updates to address this security vulnerability. Users can help keep themselves secure by applying current     updates or downloading the latest Zoom software with all current security updates from     https://zoom.us/download . (CVE-2018-15715)

Note that Nessus has not tested for this issue but has instead relied only on the application's self-reported version number.

The version of Zoom Client for Meetings installed on the remote host is prior to 4.1.34475.1105. It is, therefore, affected by a vulnerability as referenced in the ZSB-18001 advisory.

  - A vulnerability in the Zoom client could allow a remote, unauthenticated attacker to control meeting     functionality such as ejecting meeting participants, sending chat messages, and controlling participant     microphone muting. If the attacker was also a valid participant in the meeting and another participant was     sharing their desktop screen, the attacker could also take control of that participant's keyboard and     mouse. The vulnerability is due to the fact that Zoom's internal messaging pump dispatched both client     User Datagram Protocol (UDP) and server Transmission Control Protocol (TCP) messages to the same message     handler. An attacker can exploit this vulnerability to craft and send UDP packets which get interpreted as     messages processed from the trusted TCP channel used by authorized Zoom servers. Zoom released client     updates to address this security vulnerability. Users can help keep themselves secure by applying current     updates or downloading the latest Zoom software with all current security updates from     https://zoom.us/download . (CVE-2018-15715)

Note that Nessus has not tested for this issue but has instead relied only on the application's self-reported version number.

The version of Zoom Client for Meetings installed on the remote host is prior to 2.5.146186.1130. It is, therefore, affected by a vulnerability as referenced in the ZSB-18001 advisory.

  - A vulnerability in the Zoom client could allow a remote, unauthenticated attacker to control meeting     functionality such as ejecting meeting participants, sending chat messages, and controlling participant     microphone muting. If the attacker was also a valid participant in the meeting and another participant was     sharing their desktop screen, the attacker could also take control of that participant's keyboard and     mouse. The vulnerability is due to the fact that Zoom's internal messaging pump dispatched both client     User Datagram Protocol (UDP) and server Transmission Control Protocol (TCP) messages to the same message     handler. An attacker can exploit this vulnerability to craft and send UDP packets which get interpreted as     messages processed from the trusted TCP channel used by authorized Zoom servers. Zoom released client     updates to address this security vulnerability. Users can help keep themselves secure by applying current     updates or downloading the latest Zoom software with all current security updates from     https://zoom.us/download . (CVE-2018-15715)

Note that Nessus has not tested for this issue but has instead relied only on the application's self-reported version number.

The version of Zoom Client for Meetings installed on the remote Windows host is 4.x prior to 4.1.34814.1119. It is, therefore, affected by a message spoofing vulnerability. An attacker could leverage this vulnerability to perform restricted meeting operations.

The version of Zoom Client for Meetings installed on the remote macOS or Mac OS X host is 4.x prior to 4.1.34801.1116. It is, therefore, affected by a message spoofing vulnerability. An attacker could leverage this vulnerability to perform restricted meeting operations.

ID	Name	Product	Family	Severity
168824	Zoom Client for Meetings < 4.1.34460.1105 Vulnerability (ZSB-18001)	Nessus	Windows	critical
168812	Zoom Client for Meetings < 4.1.34475.1105 Vulnerability (ZSB-18001)	Nessus	MacOS X Local Security Checks	critical
168808	Zoom Client for Meetings < 2.5.146186.1130 Vulnerability (ZSB-18001)	Nessus	Misc.	critical
119242	Zoom Client for Meetings 4.x < 4.1.34814.1119 Message Spoofing Vulnerability	Nessus	Windows	critical
119241	Zoom Client for Meetings 4.x < 4.1.34801.1116 Message Spoofing Vulnerability (macOS)	Nessus	MacOS X Local Security Checks	critical

Detections

Analytics

CVE-2018-15715

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Tenable Plugins

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