CVE-2021-26736

ZApp Installer Privilege Escalation Vulnerabilities

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Published Oct 23, 2023 CVSS 3.1 · 6.7 Medium EPSS < 1% KEV · Not listed

Description

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.

Affected Products

Default status is the baseline for the product, each version can override it (e.g. patched versions marked unaffected).

Vendor Product Default status Versions

Zscaler

Client Connector

unaffected

Version	Status	Constraints
`0`	affected	< 3.6

Configuration 1 [-]

cpe:2.3:a:zscaler:client_connector:*:*:*:*:*:windows:*:*

No data.

No data available yet.

Remediation

No solution or workaround provided in the CVE record

Tracking

Sign in to view the affected projects.

Advisories

Source	ID	Title
EUVD	EUVD-2021-13523	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.

Metrics

No CVSS v4.0

Attack Vector Local

Attack Complexity High

Privileges Required Low

Scope Unchanged

Confidentiality Impact High

Integrity Impact High

Availability Impact High

User Interaction Required

No CVSS v3.0

No CVSS v2

This CVE is not in the KEV list.

Exploit prediction score: < 1% (0.227% probability within 30 days)

Exploitation none

Automatable no

Technical Impact total

References

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

History

Mar 4, 2025 3:45 AM Scoring metrics updated View changes

Type	Values Removed	Values Added
Metrics		ssvc `{'options': {'Automatable': 'no', 'Exploitation': 'none', 'Technical Impact': 'total'}, 'version': '2.0.3'}`

Subscriptions

Zscaler Client Connector

Weaknesses

Sources

CVE record Updated: Feb 27, 2025, 8:40 PM

Status: PUBLISHED
Assigner: Zscaler
Published: Oct 23, 2023, 1:21 PM
Updated: Feb 27, 2025, 8:40 PM
Reserved: Feb 5, 2021, 8:34 PM

View source JSON

Vulnrichment Updated: Aug 3, 2024, 8:33 PM

Updated: Aug 3, 2024, 8:33 PM

NVD Updated: Jun 17, 2026, 3:43 AM

Status: Modified
Published: Oct 23, 2023, 2:15 PM
Modified: Jun 17, 2026, 3:43 AM

View source JSON

Red Hat No data

No data.

OpenCVE enrichment No data

No data.

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