How severe is CVE-2021-34415?

CVE-2021-34415 has a CVSS 3.x base score of 7.5, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.

Is CVE-2021-34415 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (57th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-34415?

CVE-2021-34415 affects Zoom Meeting Connector. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2021-34415?

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-2021-34415 published?

CVE-2021-34415 was published on 2021-09-27 and last updated on 2026-06-17.

CVE-2021-34415

CVE-2021-34415 is a high-severity vulnerability in Zoom Meeting Connector with a CVSS 3.x base score of 7.5. 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-770.

Key facts

Severity: High (CVSS 3.x base score 7.5)
CVSS v2: 7.8
EPSS exploit prediction: 1% (57th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-770
Affected product: Zoom Meeting Connector
Published: 2021-09-27
Last modified: 2026-06-17

Description

The Zone Controller service in the Zoom On-Premise Meeting Connector Controller before version 4.6.358.20210205 does not verify the cnt field sent in incoming network packets, which leads to exhaustion of resources and system crash.

Frequently asked questions

What is CVE-2021-34415?: The Zone Controller service in the Zoom On-Premise Meeting Connector Controller before version 4.6.358.20210205 does not verify the cnt field sent in incoming network packets, which leads to exhaustion of resources and system crash.
How severe is CVE-2021-34415?: CVE-2021-34415 has a CVSS 3.x base score of 7.5, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.
Is CVE-2021-34415 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (57th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-34415?: CVE-2021-34415 affects Zoom Meeting Connector. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2021-34415?: 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-2021-34415 published?: CVE-2021-34415 was published on 2021-09-27 and last updated on 2026-06-17.

References

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

Affected products (1)

cpe:2.3:a:zoom:meeting_connector:*:*:*:*:*:*:*:*

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