Zoom Client for Meetings buffer overflow

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
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A vulnerability was found in Zoom Client for Meetings, Rooms for Conference Room, Controllers for Zoom Rooms, VDI, SDK, Meeting SDK, Video SDK, On-Premise Meeting Connector Controller, On-Premise Meeting Connector MMR, On-Premise Recording Connector, On-Premise Virtual Room Connector, On-Premise Virtual Room Connector Load Balancer, Hybrid Zproxy and Hybrid MMR (Unified Communication Software). It has been rated as critical. This issue affects an unknown part. The manipulation with an unknown input leads to a memory corruption vulnerability. Using CWE to declare the problem leads to CWE-120. Impacted is confidentiality, integrity, and availability. The summary by CVE is:

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 before version 5.8.4, Zoom Meeting SDK for Android before version, Zoom Meeting SDK for iOS before version, Zoom Meeting SDK for macOS before version, Zoom Meeting SDK for Windows before version, Zoom Video SDK (for Android, iOS, macOS, and Windows) before version 1.1.2, Zoom On-Premise Meeting Connector Controller before version, Zoom On-Premise Meeting Connector MMR before version, Zoom On-Premise Recording Connector before version, 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.

The weakness was presented 11/25/2021. The advisory is shared at explore.zoom.us. The identification of this vulnerability is CVE-2021-34423 since 06/09/2021. The exploitation is known to be easy. The attack may be initiated remotely. No form of authentication is needed for a successful exploitation. Neither technical details nor an exploit are publicly available. The price for an exploit might be around USD $0-$5k at the moment (estimation calculated on 11/27/2021).

Upgrading eliminates this vulnerability.





CPE 2.3infoedit

CPE 2.2infoedit


VulDB Meta Base Score: 7.3
VulDB Meta Temp Score: 7.1

VulDB Base Score: 7.3
VulDB Temp Score: 7.0
VulDB Vector: 🔒
VulDB Reliability: 🔍

CNA Base Score: 7.3
CNA Vector (Zoom Video Communications, Inc.): 🔒



VulDB Base Score: 🔒
VulDB Temp Score: 🔒
VulDB Reliability: 🔍


Class: Memory corruption
CWE: CWE-120
ATT&CK: Unknown

Local: No
Remote: Yes

Availability: 🔒
Status: Not defined
Price Prediction: 🔍
Current Price Estimation: 🔒


Threat Intelligenceinfoedit

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍


Recommended: Upgrade
Status: 🔍

0-Day Time: 🔒

Upgrade: explore.zoom.us


06/09/2021 CVE assigned
11/25/2021 +169 days Advisory disclosed
11/25/2021 +0 days VulDB entry created
11/27/2021 +2 days VulDB last update


Advisory: explore.zoom.us
Status: Confirmed

CVE: CVE-2021-34423 (🔒)


Created: 11/25/2021 07:37 AM
Updated: 11/27/2021 09:06 PM
Changes: (1) source_cve_nvd_summary
Complete: 🔍


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