CVE-2023-28803
CVE-2023-28803 is a medium-severity vulnerability in Zscaler Client Connector with a CVSS 3.x base score of 5.9. 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-290.
Key facts
- Severity: Medium (CVSS 3.x base score 5.9)
- EPSS exploit prediction: 0% (17th percentile)
- Actively exploited: Not listed in CISA KEV
- Weakness: CWE-290
- Affected product: Zscaler Client Connector
- Published:
- Last modified:
Description
An authentication bypass by spoofing of a device with a synthetic IP address is possible in Zscaler Client Connector on Windows, allowing a functionality bypass. This issue affects Client Connector: before 3.9.
Frequently asked questions
- What is CVE-2023-28803?
- An authentication bypass by spoofing of a device with a synthetic IP address is possible in Zscaler Client Connector on Windows, allowing a functionality bypass. This issue affects Client Connector: before 3.9.
- How severe is CVE-2023-28803?
- CVE-2023-28803 has a CVSS 3.x base score of 5.9, rated medium severity. It is exploitable over an adjacent network with high attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity low, and availability none.
- Is CVE-2023-28803 being actively exploited?
- It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (17th percentile), an estimate of the probability of exploitation in the next 30 days.
- What products are affected by CVE-2023-28803?
- CVE-2023-28803 affects Zscaler Client Connector. See the affected-products list for the exact vulnerable versions.
- How do I fix CVE-2023-28803?
- Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
- When was CVE-2023-28803 published?
- CVE-2023-28803 was published on 2023-10-23 and last updated on 2026-06-17.
References
Affected products (1)
- cpe:2.3:a:zscaler:client_connector:*:*:*:*:*:windows:*:*
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