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Vulnerability record · CVE-2021-34418 · published 11 November 2021

CVE-2021-34418: Zoom on-premise meeting connector controller null pointer dereference vulnerability

Zoom · Zoom On Premise Meeting Connector Controller

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.

5.3 CVSS 3.1 Medium EPSS 0.63% · top 51.4% CWE-476 · NULL pointer dereference
5.3CVSS 3.1 base score, v2 5.0
0.63%EPSS exploitation probability, 30 days
NoNot in CISA KEV
5Affected product versions listed by NVD
2References
17 Jun 2026Last modified by NVD

Description

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.

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

Affected products

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

References

LinkTags
https://explore.zoom.us/en/trust/security/security-bulletin Vendor Advisory
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.

9.8CVE-2021-34423Zoom meetings classic buffer overflow vulnerabilityA buffer overflow vulnerability was discovered in Zoom Client for Meetings (for Android, iOS, Linux, macOS, and Windows) before version 5.8.4, Zoom C…EPSS 3.3%8.6CVE-2022-28759Zoom on-premise meeting connector mmr improper access control vulnerabilityZoom On-Premise Meeting Connector MMR before version 4.8.20220815.130 contains an improper access control vulnerability. As a result, a malicious act…EPSS 0.68%8.2CVE-2022-28758Zoom on-premise meeting connector mmr improper access control vulnerabilityZoom On-Premise Meeting Connector MMR before version 4.8.20220815.130 contains an improper access control vulnerability. As a result, a malicious act…EPSS 0.69%7.5CVE-2022-22783Zoom on-premise meeting connector controller vulnerabilityA vulnerability in Zoom On-Premise Meeting Connector Controller version 4.8.102.20220310 and On-Premise Meeting Connector MMR version 4.8.102.2022031…EPSS 1.0%7.5CVE-2021-34424Zoom meetings out-of-bounds read vulnerabilityA vulnerability was discovered in the Zoom Client for Meetings (for Android, iOS, Linux, macOS, and Windows) before version 5.8.4, Zoom Client for Me…EPSS 1.7%7.2CVE-2021-34417Zoom on-premise meeting connector controller improper input validation vulnerabilityThe network proxy page on the web portal for the Zoom On-Premise Meeting Connector Controller before version 4.6.365.20210703, Zoom On-Premise Meetin…EPSS 1.2%6.5CVE-2022-28761Zoom on-premise meeting connector mmr improper access control vulnerabilityZoom On-Premise Meeting Connector MMR before version 4.8.20220916.131 contains an improper access control vulnerability. As a result, a malicious act…EPSS 0.76%6.5CVE-2022-28760Zoom on-premise meeting connector mmr improper access control vulnerabilityZoom On-Premise Meeting Connector MMR before version 4.8.20220815.130 contains an improper access control vulnerability. As a result, a malicious act…EPSS 0.63%

Source: NIST National Vulnerability Database (record CVE-2021-34418), CISA KEV, FIRST EPSS (scores of 2026-10-12). This page is refreshed as NVD updates the record.