Client Connector
CVE-2021-26737: Privilege Escalation Using PID Reuse in ZCC macOS
The Zscaler Client Connector for macOS prior to 3.6 did not sufficiently validate RPC clients.
Published
ExploitedNot in CISA KEV
Ransomware useNot reportedPer CISA
SeverityMEDIUMCVSS 3.1 5.5
EPSS0.11%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 | 3.6 or later |
Always confirm against the vendor advisory, which lists every fixed hotfix.
What it is
The Zscaler Client Connector for macOS prior to 3.6 did not sufficiently validate RPC clients. A local adversary without sufficient privileges may be able to shutdown the Zscaler tunnel by exploiting a race condition.
Sources
KEV status, EPSS score and vendor data refreshed automatically, last on 13 Oct 2026.