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CVE-2021-33907
The Zoom Client for Meetings for Windows in all versions before 5.3.0 fails to properly validate the certificate information used to sign…
Critical9.8EPSS 4.0%
- Published
- Updated
- Reserved
- Assigned by
- Zoom
Description
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.
Timeline
ID reserved
By Zoom
- 4 months later
· 4 months later
Published
- 3 years later
· 3 years later
Record updated
Changes after publication (a new score, a public exploit, EPSS crossing 1, 10 or 50 %, leaving KEV) are kept since November 2026; earlier ones are not known.
Scores
| Scored by | CVSS | Score | Vector |
|---|---|---|---|
| NVDNVD · Modified | 3.1 | Critical9.8 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H |
- EPSS (exploitation in 30 days)
- 4.0% · top 9.4% of all CVEs (7 Nov 2026)
Loading the EPSS history…
The list uses the assigner's score when there is one, then CISA's, then NVD's: Critical 9.8.
Weakness
- Improper Verification of Crypto Signature
- CWE-295 (opens in a new tab)All about CWE-295 and its CVEs
Affected products
Zoom Client for Meetings for Windows
- affected All versions of the Zoom Client for Meetings for Windows before version 5.3.0
References (1)
- https://explore.zoom.us/en/trust/security/security-bulletin/ (opens in a new tab)x_refsource_MISCx_transferred
Sources
The same CVE in the primary databases and aggregators, to check against.
- CVE.org record (opens in a new tab)
- CVE List JSON (GitHub) (opens in a new tab)
- NVD (opens in a new tab)
- FIRST EPSS (opens in a new tab)
- OSV.dev (opens in a new tab)
- GitHub Advisories (opens in a new tab)
- CIRCL Vulnerability-Lookup (opens in a new tab)
Badge for a README or a ticket
[](https://trackcve.app/cve/CVE-2021-33907)Record last updated .