How severe is CVE-2021-34408?

CVE-2021-34408 has a CVSS 3.x base score of 7.8, rated high severity. It is exploitable over local access with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.

Is CVE-2021-34408 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (36th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-34408?

CVE-2021-34408 affects Zoom Meetings. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2021-34408?

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-2021-34408 published?

CVE-2021-34408 was published on 2021-09-27 and last updated on 2026-06-17.

CVE-2021-34408

CVE-2021-34408 is a high-severity vulnerability in Zoom Meetings with a CVSS 3.x base score of 7.8. 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-59.

Key facts

Severity: High (CVSS 3.x base score 7.8)
CVSS v2: 4.6
EPSS exploit prediction: 0% (36th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-59
Affected product: Zoom Meetings
Published: 2021-09-27
Last modified: 2026-06-17

Description

The Zoom Client for Meetings for Windows in all versions before version 5.3.2 writes log files to a user writable directory as a privileged user during the installation or update of the client. This could allow for potential privilege escalation if a link was created between the user writable directory used and a non-user writable directory.

Frequently asked questions

What is CVE-2021-34408?: The Zoom Client for Meetings for Windows in all versions before version 5.3.2 writes log files to a user writable directory as a privileged user during the installation or update of the client. This could allow for potential privilege escalation if a link was created between the user writable directory used and a non-user writable directory.
How severe is CVE-2021-34408?: CVE-2021-34408 has a CVSS 3.x base score of 7.8, rated high severity. It is exploitable over local access with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2021-34408 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (36th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-34408?: CVE-2021-34408 affects Zoom Meetings. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2021-34408?: 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-2021-34408 published?: CVE-2021-34408 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:meetings:*:*:*:*:*:windows:*:*

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