ZApp Installer Privilege Escalation Vulnerabilities

published 2023-10-23 3 y ago modified 2026-06-17 4 mo ago also EUVD-2021-13523

cvss: 6.7; version 3.1, CNA
cisa kev: Not listed; not in CISA's catalog
epss: 0.2%; EPSS 0.2% chance of exploitation in 30 days, percentile 13%
public exploits: 0; none known

Multiple vulnerabilities in the Zscaler Client Connector Installer and Uninstaller for Windows prior to 3.6 allowed execution of binaries from a low privileged path. A local adversary may be able to execute code with SYSTEM privileges.

Patch / fix

fixed in 1

Zscaler Client Connector 3.6

CISA SSVC

Exploitation: none
Automatable: no
Technical impact: total
Assessed: 20 mo ago (2025-02-26)

Exploit prediction

0.23% chance of exploitation in the next 30 days, higher than 13% of all scored CVEs (FIRST EPSS, 2026-11-08).

CVSS scores

assigned by	version	score	vector
CNA	3.1	6.7	CVSS:3.1/AV:L/AC:H/PR:L/UI:R/S:U/C:H/I:H/A:H
NVD	3.1	7.8	CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

Affected products

Zscaler Client Connector

Classification

Weakness

CWE-20 Improper Input Validation
CWE-22 Improper Limitation of a Pathname to a Restricted Directory

References

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

Sources

CVE List CVE-2021-26736
NVD CVE-2021-26736

Fencer Vulns keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.

Summary