Client Connector
CVE-2023-28803: Traffic being bypassed by ZCC by configuring synthetic IP range as local network
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.
Published
ExploitedNot in CISA KEV
Ransomware useNot reportedPer CISA
SeverityMEDIUMCVSS 3.1 5.9
EPSS0.26%Chance of exploitation in 30 days
Public exploitNot tracked
FixAvailable
Automatic summary from the vendor's CVE record. We haven't written a full analysis of this vulnerability yet.
Affected and fixed versions
| Product / branch | Fixed in |
|---|---|
| Client Connector 0 | 3.9 or later |
Always confirm against the vendor advisory, which lists every fixed hotfix.
What it is
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.
Sources
KEV status, EPSS score and vendor data refreshed automatically, last on 13 Oct 2026.