How severe is CVE-2023-28806?

CVE-2023-28806 has a CVSS 3.x base score of 5.7, rated medium severity. It is exploitable over local access with high attack complexity, requires high privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability none.

Is CVE-2023-28806 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (9th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2023-28806?

CVE-2023-28806 affects Zscaler Client Connector. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2023-28806?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.

Does CVE-2023-28806 have an EU (EUVD) identifier?

Yes. CVE-2023-28806 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2023-32441.

When was CVE-2023-28806 published?

CVE-2023-28806 was published on 2024-08-06 and last updated on 2026-06-17.

CVE-2023-28806

CVE-2023-28806 is a medium-severity vulnerability in Zscaler Client Connector with a CVSS 3.x base score of 5.7. 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-347.

Key facts

Severity: Medium (CVSS 3.x base score 5.7)
EPSS exploit prediction: 0% (9th percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2023-32441
Weakness: CWE-347
Affected product: Zscaler Client Connector
Published: 2024-08-06
Last modified: 2026-06-17

Description

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.

Frequently asked questions

What is CVE-2023-28806?: 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.
How severe is CVE-2023-28806?: CVE-2023-28806 has a CVSS 3.x base score of 5.7, rated medium severity. It is exploitable over local access with high attack complexity, requires high privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability none.
Is CVE-2023-28806 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (9th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2023-28806?: CVE-2023-28806 affects Zscaler Client Connector. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2023-28806?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
Does CVE-2023-28806 have an EU (EUVD) identifier?: Yes. CVE-2023-28806 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2023-32441.
When was CVE-2023-28806 published?: CVE-2023-28806 was published on 2024-08-06 and last updated on 2026-06-17.

References

https://help.zscaler.com/client-connector/client-connector-app-release-summary-2023?applicable_category=windows&applicable_version=4.2.0.190

Affected products (1)

cpe:2.3:a:zscaler:client_connector:*:*:*:*:*:windows:*:*

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