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Vulnerability record · CVE-2021-34424 · published 24 November 2021

CVE-2021-34424: Zoom meetings out-of-bounds read vulnerability

Zoom · Meetings

A vulnerability was discovered in the Zoom Client for Meetings (for Android, iOS, Linux, macOS, and Windows) before version 5.8.4, Zoom Client for Meetings for Blackberry (for Android and iOS) before version 5.8.1, Zoom Client for Meetings for intune (for Android and iOS) before version 5.8.4, Zoom Client for Meetings for Chrome OS before version 5.0.1, Zoom Rooms for Conference Room (for Android, AndroidBali, macOS, and Windows) before version 5.8.3, Controllers for Zoom Rooms (for Android, iOS, and Windows) before version 5.8.3, Zoom VDI Windows Meeting Client before version 5.8.4, Zoom VDI Azure Virtual Desktop Plugins (for Windows x86 or x64, IGEL x64, Ubuntu x64, HP ThinPro OS x64) before version 5.8.4.21112, Zoom VDI Citrix Plugins (for Windows x86 or x64, Mac Universal Installer & Uninstaller, IGEL x64, eLux RP6 x64, HP ThinPro OS x64, Ubuntu x64, CentOS x 64, Dell ThinOS) before version 5.8.4.21112, Zoom VDI VMware Plugins (for Windows x86 or x64, Mac Universal Installer & Uninstaller, IGEL x64, eLux RP6 x64, HP ThinPro OS x64, Ubuntu x64, CentOS x 64, Dell ThinOS) before version 5.8.4.21112, Zoom Meeting SDK for Android before version 5.7.6.1922, Zoom Meeting SDK for iOS before version 5.7.6.1082, Zoom Meeting SDK for macOS before version 5.7.6.1340, Zoom Meeting SDK for Windows before version 5.7.6.1081, Zoom Video SDK (for Android, iOS, macOS, and Windows) before version 1.1.2, Zoom on-premise Meeting Connector before version 4.8.12.20211115, Zoom on-premise Meeting Connector MMR before version 4.8.12.20211115, Zoom on-premise Recording Connector before version 5.1.0.65.20211116, Zoom on-premise Virtual Room Connector before version 4.4.7266.20211117, Zoom on-premise Virtual Room Connector Load Balancer before version 2.5.5692.20211117, Zoom Hybrid Zproxy before version 1.0.1058.20211116, and Zoom Hybrid MMR before version 4.6.20211116.131_x86-64 which potentially allowed for the exposure of the state of process memory. This issue could be used to potentially gain insight into arbitrary areas of the product's memory.

7.5 CVSS 3.1 High EPSS 1.7% · top 23.4% CWE-125 · Out-of-bounds read
7.5CVSS 3.1 base score, v2 5.0
1.7%EPSS exploitation probability, 30 days
NoNot in CISA KEV
25Affected product versions listed by NVD
4References
17 Jun 2026Last modified by NVD

Description

A vulnerability was discovered in the Zoom Client for Meetings (for Android, iOS, Linux, macOS, and Windows) before version 5.8.4, Zoom Client for Meetings for Blackberry (for Android and iOS) before version 5.8.1, Zoom Client for Meetings for intune (for Android and iOS) before version 5.8.4, Zoom Client for Meetings for Chrome OS before version 5.0.1, Zoom Rooms for Conference Room (for Android, AndroidBali, macOS, and Windows) before version 5.8.3, Controllers for Zoom Rooms (for Android, iOS, and Windows) before version 5.8.3, Zoom VDI Windows Meeting Client before version 5.8.4, Zoom VDI Azure Virtual Desktop Plugins (for Windows x86 or x64, IGEL x64, Ubuntu x64, HP ThinPro OS x64) before version 5.8.4.21112, Zoom VDI Citrix Plugins (for Windows x86 or x64, Mac Universal Installer & Uninstaller, IGEL x64, eLux RP6 x64, HP ThinPro OS x64, Ubuntu x64, CentOS x 64, Dell ThinOS) before version 5.8.4.21112, Zoom VDI VMware Plugins (for Windows x86 or x64, Mac Universal Installer & Uninstaller, IGEL x64, eLux RP6 x64, HP ThinPro OS x64, Ubuntu x64, CentOS x 64, Dell ThinOS) before version 5.8.4.21112, Zoom Meeting SDK for Android before version 5.7.6.1922, Zoom Meeting SDK for iOS before version 5.7.6.1082, Zoom Meeting SDK for macOS before version 5.7.6.1340, Zoom Meeting SDK for Windows before version 5.7.6.1081, Zoom Video SDK (for Android, iOS, macOS, and Windows) before version 1.1.2, Zoom on-premise Meeting Connector before version 4.8.12.20211115, Zoom on-premise Meeting Connector MMR before version 4.8.12.20211115, Zoom on-premise Recording Connector before version 5.1.0.65.20211116, Zoom on-premise Virtual Room Connector before version 4.4.7266.20211117, Zoom on-premise Virtual Room Connector Load Balancer before version 2.5.5692.20211117, Zoom Hybrid Zproxy before version 1.0.1058.20211116, and Zoom Hybrid MMR before version 4.6.20211116.131_x86-64 which potentially allowed for the exposure of the state of process memory. This issue could be used to potentially gain insight into arbitrary areas of the product's memory.

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N

Affected products

25 vulnerable configurations from NVD's CPE data, grouped by vendor and product.

References

LinkTags
http://packetstormsecurity.com/files/165419/Zoom-MMR-Server-Information-Leak.html Third Party AdvisoryVDB Entry
https://explore.zoom.us/en/trust/security/security-bulletin Vendor Advisory
http://packetstormsecurity.com/files/165419/Zoom-MMR-Server-Information-Leak.html Third Party AdvisoryVDB Entry
https://explore.zoom.us/en/trust/security/security-bulletin Vendor Advisory

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Related vulnerabilities

Same products first, then exploited flaws of the same weakness class.

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Source: NIST National Vulnerability Database (record CVE-2021-34424), CISA KEV, FIRST EPSS (scores of 2026-09-27). This page is refreshed as NVD updates the record.