Signature validation error in DLL allows disabling anti-tampering protection

published 2024-08-06 2 y ago modified 2026-06-17 4 mo ago also EUVD-2023-32441

cvss: 5.7; version 3.1, CNA
cisa kev: Not listed; not in CISA's catalog
epss: 0.2%; EPSS 0.2% chance of exploitation in 30 days, percentile 8%
public exploits: 0; none known

An Improper Validation of signature in Zscaler Client Connector on Windows allows an authenticated user to disable anti-tampering. This issue affects Client Connector on Windows <4.2.0.190.

Patch / fix

fixed in 2

Zscaler Client Connector 4.2.0.190
zscaler client_connector 4.2.0.190

CISA SSVC

Exploitation: none
Automatable: no
Technical impact: total
Assessed: 2 y ago (2024-08-06)

Exploit prediction

0.19% chance of exploitation in the next 30 days, higher than 8% of all scored CVEs (FIRST EPSS, 2026-11-08).

CVSS scores

assigned by	version	score	vector
CNA	3.1	5.7	CVSS:3.1/AV:L/AC:H/PR:H/UI:N/S:U/C:H/I:H/A:N
NVD	3.1	6.5	CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:N

Affected products

Zscaler Client Connector
zscaler client_connector

Classification

Weakness

CWE-347 Improper Verification of Cryptographic Signature

References

help.zscaler.com /client-connector/client-connector-app-release-summary-2023?applicable_category=windows&applicable_version=4.2
vendor-advisory

Sources

CVE List CVE-2023-28806
NVD CVE-2023-28806

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Summary