How severe is CVE-2021-34417?

CVE-2021-34417 has a CVSS 3.x base score of 7.9, rated high severity. It is exploitable over local access with low attack complexity, requires high privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability none.

Is CVE-2021-34417 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (66th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-34417?

CVE-2021-34417 primarily affects Zoom Zoom On-premise Meeting Connector Controller. In total, 5 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2021-34417?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.

When was CVE-2021-34417 published?

CVE-2021-34417 was published on 2021-11-11 and last updated on 2026-06-17.

CVE-2021-34417

CVE-2021-34417 is a high-severity vulnerability in Zoom Zoom On-premise Meeting Connector Controller with a CVSS 3.x base score of 7.9. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-20.

Key facts

Severity: High (CVSS 3.x base score 7.9)
CVSS v2: 9.0
EPSS exploit prediction: 1% (66th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-20
Affected product: Zoom Zoom On-premise Meeting Connector Controller
Published: 2021-11-11
Last modified: 2026-06-17

Description

The network proxy page on the web portal for the Zoom On-Premise Meeting Connector Controller before version 4.6.365.20210703, Zoom On-Premise Meeting Connector MMR before version 4.6.365.20210703, Zoom On-Premise Recording Connector before version 3.8.45.20210703, Zoom On-Premise Virtual Room Connector before version 4.4.6868.20210703, and Zoom On-Premise Virtual Room Connector Load Balancer before version 2.5.5496.20210703 fails to validate input sent in requests to set the network proxy password. This could lead to remote command injection by a web portal administrator.

Frequently asked questions

What is CVE-2021-34417?: The network proxy page on the web portal for the Zoom On-Premise Meeting Connector Controller before version 4.6.365.20210703, Zoom On-Premise Meeting Connector MMR before version 4.6.365.20210703, Zoom On-Premise Recording Connector before version 3.8.45.20210703, Zoom On-Premise Virtual Room Connector before version 4.4.6868.20210703, and Zoom On-Premise Virtual Room Connector Load Balancer before version 2.5.5496.20210703 fails to validate input sent in requests to set the network proxy password. This could lead to remote command injection by a web portal administrator.
How severe is CVE-2021-34417?: CVE-2021-34417 has a CVSS 3.x base score of 7.9, rated high severity. It is exploitable over local access with low attack complexity, requires high privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability none.
Is CVE-2021-34417 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (66th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-34417?: CVE-2021-34417 primarily affects Zoom Zoom On-premise Meeting Connector Controller. In total, 5 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2021-34417?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
When was CVE-2021-34417 published?: CVE-2021-34417 was published on 2021-11-11 and last updated on 2026-06-17.

References

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

Affected products (5)

cpe:2.3:a:zoom:zoom_on-premise_meeting_connector_controller:*:*:*:*:*:*:*:*
cpe:2.3:a:zoom:zoom_on-premise_meeting_connector_mmr:*:*:*:*:*:*:*:*
cpe:2.3:a:zoom:zoom_on-premise_recording_connector:*:*:*:*:*:*:*:*
cpe:2.3:a:zoom:zoom_on-premise_virtual_room_connector:*:*:*:*:*:*:*:*
cpe:2.3:a:zoom:zoom_on-premise_virtual_room_connector_load_balancer:*:*:*:*:*:*:*:*

More vulnerabilities in Zoom Zoom On-premise Meeting Connector Controller

CVE-2021-34423 — Critical (CVSS 9.8): A buffer overflow vulnerability was discovered in Zoom Client for Meetings (for Android, iOS, Linux, macOS, and…
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CVE-2021-34418 — Medium (CVSS 4.0): The login routine of the web console in the Zoom On-Premise Meeting Connector before version 4.6.239.20200613, Zoom…

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