How severe is CVE-2023-28804?

CVE-2023-28804 has a CVSS 3.x base score of 8.2, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity low, and availability none.

Is CVE-2023-28804 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (15th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2023-28804?

CVE-2023-28804 affects Zscaler Client Connector. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2023-28804?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.

When was CVE-2023-28804 published?

CVE-2023-28804 was published on 2023-10-23 and last updated on 2026-06-17.

CVE-2023-28804

CVE-2023-28804 is a high-severity vulnerability in Zscaler Client Connector with a CVSS 3.x base score of 8.2. 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: High (CVSS 3.x base score 8.2)
EPSS exploit prediction: 0% (15th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-347
Affected product: Zscaler Client Connector
Published: 2023-10-23
Last modified: 2026-06-17

Description

An Improper Verification of Cryptographic Signature vulnerability in Zscaler Client Connector on Linux allows replacing binaries.This issue affects Linux Client Connector: before 1.4.0.105

Frequently asked questions

What is CVE-2023-28804?: An Improper Verification of Cryptographic Signature vulnerability in Zscaler Client Connector on Linux allows replacing binaries.This issue affects Linux Client Connector: before 1.4.0.105
How severe is CVE-2023-28804?: CVE-2023-28804 has a CVSS 3.x base score of 8.2, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity low, and availability none.
Is CVE-2023-28804 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (15th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2023-28804?: CVE-2023-28804 affects Zscaler Client Connector. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2023-28804?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
When was CVE-2023-28804 published?: CVE-2023-28804 was published on 2023-10-23 and last updated on 2026-06-17.

References

https://help.zscaler.com/client-connector/client-connector-app-release-summary-2023

Affected products (1)

cpe:2.3:a:zscaler:client_connector:*:*:*:*:*:linux:*:*

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