CVE-2021-34423

high-risk
Published 2021-11-24

A buffer overflow vulnerability was discovered in 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 Controller 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. This can potentially allow a malicious actor to crash the service or application, or leverage this vulnerability to execute arbitrary code.

Do I need to act?

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0.39% chance of exploitation
EPSS score — low exploit probability
-
Not on CISA KEV list
No confirmed active exploitation reported to CISA
?
Patch status unknown
Check vendor advisories for fix availability and mitigation guidance
9
CVSS 9.8/10 Critical
NETWORK / LOW complexity

Affected Products (20)

Meetings For Blackberry
Meetings For Intune
Meetings For Chrome Os
Rooms For Conference Rooms
Controllers For Zoom Rooms
Android Meeting Sdk
Iphone Os Meeting Sdk
Macos Meeting Sdk
Windows Meeting Sdk
Android Video Sdk
Iphone Os Video Sdk
Macos Video Sdk
Windows Video Sdk
Hybrid Mmr
Hybrid Zproxy
Zoom On-Premise Meeting Connector Controller
Zoom On-Premise Meeting Connector Mmr
Zoom On-Premise Recording Connector

Affected Vendors

Zoom

References (4)

Third Party Advisory http://packetstormsecurity.com/files/165417/Zoom-Chat-Message-Processing-Buffer-...
Vendor Advisory https://explore.zoom.us/en/trust/security/security-bulletin
Third Party Advisory http://packetstormsecurity.com/files/165417/Zoom-Chat-Message-Processing-Buffer-...
Vendor Advisory https://explore.zoom.us/en/trust/security/security-bulletin
54
/ 100
high-risk
Severity 32/34 · Critical
Exploitability 1/34 · Minimal
Exposure 21/34 · High