CVE-2021-26734: Junction Delete leading to elevation of privilege

Severity: medium (CVSS 5.5 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.2% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2023-10-23 · updated 2026-06-17
Weakness: CWE-269

Description

Zscaler Client Connector Installer on Windows before version 3.4.0.124 improperly handled directory junctions during uninstallation. A local adversary may be able to delete folders in an elevated context.

Affected products

Zscaler Client Connector: before 3.4.0.124 — fixed in 3.4.0.124

How to fix

Upgrade to a fixed version: Zscaler Client Connector 3.4.0.124. Check the vendor advisory for mitigations.

References

https://help.zscaler.com/zscaler-client-connector/client-connector-app-release-summary-2021
https://help.zscaler.com/zscaler-client-connector/client-connector-app-release-summary-2021

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