CVE-2023-28602

Component downgrade via improper signature verification

Published Jun 13, 2023 · Updated Jan 2, 2025

Improper signature verification in Zoom for Windows Client before 5.13.5 allows local users to downgrade client components. Zoom has not disclosed the affected verification routine, the signed object, or the precise signature-check failure. A low-privileged local user must satisfy a high-complexity condition; success rolls installed components back to earlier code and weakens update integrity.

CVSS severity2.8
Low
EPSS probability0.31%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Improper signature verification in Zoom for Windows Client before 5.13.5 allows local users to downgrade client components. Zoom has not disclosed the affected verification routine, the signed object, or the precise signature-check failure. A low-privileged local user must satisfy a high-complexity condition; success rolls installed components back to earlier code and weakens update integrity.

The record

CVE
CVE-2023-28602
Published
Jun 13, 2023
Updated
Jan 2, 2025
Vendor
Zoom Video Communications, Inc.
Product
Zoom Workplace Desktop App
Classifications
CWE-347, CAPEC-554
Attack vector
local
Privileges
authenticated

Timeline

How it unfolded

  1. Jun 13, 2023CVE publishedPublication date reported by the CVE source.
  2. Jan 2, 2025Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=before 5.13.5

What conditions does exploitation require?

Attack vectorlocal
Required privilegesauthenticated

What is affected?

Zoom Video Communications, Inc. · Zoom Workplace Desktop Appversion=before 5.13.5

Published CVSS scores

7.7NISTCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:N/I:H/A:N
2.8Zoom Video Communications, Inc.CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:C/C:N/I:L/A:N

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectorlocal
Privilegesauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-347Improper Verification of Cryptographic Signature
CAPEC-554Functionality Bypass

Public exploit references

No public exploit references are available in this record.

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

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Your stack

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