How severe is CVE-2023-28799?

CVE-2023-28799 has a CVSS 3.x base score of 8.2, rated high severity. It is exploitable over network with high attack complexity, requires low privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability none.

Is CVE-2023-28799 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (36th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2023-28799?

CVE-2023-28799 primarily affects Zscaler Client Connector. In total, 6 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2023-28799?

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-2023-28799 published?

CVE-2023-28799 was published on 2023-06-22 and last updated on 2026-06-17.

CVE-2023-28799

CVE-2023-28799 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-601.

Key facts

Severity: High (CVSS 3.x base score 8.2)
EPSS exploit prediction: 0% (36th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-601
Affected product: Zscaler Client Connector
Published: 2023-06-22
Last modified: 2026-06-17

Description

A URL parameter during login flow was vulnerable to injection. An attacker could insert a malicious domain in this parameter, which would redirect the user after auth and send the authorization token to the redirected domain.

Frequently asked questions

What is CVE-2023-28799?: A URL parameter during login flow was vulnerable to injection. An attacker could insert a malicious domain in this parameter, which would redirect the user after auth and send the authorization token to the redirected domain.
How severe is CVE-2023-28799?: CVE-2023-28799 has a CVSS 3.x base score of 8.2, rated high severity. It is exploitable over network with high attack complexity, requires low privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability none.
Is CVE-2023-28799 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (36th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2023-28799?: CVE-2023-28799 primarily affects Zscaler Client Connector. In total, 6 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2023-28799?: 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-2023-28799 published?: CVE-2023-28799 was published on 2023-06-22 and last updated on 2026-06-17.

References

Affected products (6)

cpe:2.3:a:zscaler:client_connector:*:*:*:*:*:linux:*:*
cpe:2.3:a:zscaler:client_connector:*:*:*:*:*:iphone_os:*:*
cpe:2.3:a:zscaler:client_connector:*:*:*:*:*:chrome_os:*:*
cpe:2.3:a:zscaler:client_connector:*:*:*:*:*:android:*:*
cpe:2.3:a:zscaler:client_connector:*:*:*:*:*:windows:*:*
cpe:2.3:a:zscaler:client_connector:*:*:*:*:*:macos:*:*

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