CVE-2021-33907

highpriority · track · 40EPSS 0.040 · 91 %ileEUUS

grimoire priorityP2 · Scheduled

Exploitable?

—

no known exploitation

Likely / severe?

4.01% (91st) EPSS

CVSS 10 · high

Is it mine?

2 products

Check your exposure

Who says so?

3 sources

cnnvd · enisa_euvd · nvd

EPSS · scored 2026-10-27

The Zoom Client for Meetings for Windows in all versions before 5.3.0 fails to properly validate the certificate information used to sign .msi files when performing an update of the client. This could lead to remote code execution in an elevated privileged context.

cvss

Technical severity, 0–10. One row per scoring source.

10.0

010

base score 0–10 · higher = more severe · hover a vector to decode⚠ sources disagree · high–critical · 9–10

v2.010highAV:N/AC:L/Au:N/C:C/I:C/A:Cprimary · NVD / NIST USexploitability 10 · impact 10

v3.19.8criticalCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:Hprimary · NVD / NIST USexploitability 3.9 · impact 5.9

v3.19criticalCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H/E:Usecondary · CVSS-BT (t0sche)

weaknesses

The CWE weakness classes this flaw belongs to.

CWE-295USprimary

affected products (2)

Products and version ranges known to be affected.

n/a Zoom Client for Meetings for Windows≤ All versions of the Zoom Client for Meetings for Windows before version 5.3.0enisa_euvdEU
zoom meetings< 5.3.0nvdUScpe:2.3:a:zoom:meetings:*:*:*:*:*:*:*:*

also known as (3)

Other names and identifiers for this entity.

sources

Which sources assert this record, and when.

cnnvd enisa_euvd nvd NVD CVE.org MITRE

published 2021-09-27modified 2026-06-17

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+1889 more

references (4)

External citations — patches, advisories, analysis.

scry

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