VDB-243166 · CVE-2021-26734 · GCVE-0-2021-26734

Zscaler Client Connector Installer prior 3.4.0.124 on Windows Uninstallation privileges management

CVSS Meta Temp Score CVSS is a standardized scoring system to determine possibilities of attacks. The Temp Score considers temporal factors like disclosure, exploit and countermeasures. The unique Meta Score calculates the average score of different sources to provide a normalized scoring system.	Current Exploit Price (≈) Our analysts are monitoring exploit markets and are in contact with vulnerability brokers. The range indicates the observed or calculated exploit price to be seen on exploit markets. A good indicator to understand the monetary effort required for and the popularity of an attack.	CTI Interest Score Our Cyber Threat Intelligence team is monitoring different web sites, mailing lists, exploit markets and social media networks. The CTI Interest Score identifies the interest of attackers and the security community for this specific vulnerability in real-time. A high score indicates an elevated risk to be targeted for this vulnerability.
4.1	$0-$5k	0.00

Summaryinfo

A vulnerability classified as critical was found in Zscaler Client Connector Installer on Windows. Affected by this vulnerability is an unknown functionality of the component Uninstallation Handler. Executing a manipulation can lead to privileges management. This vulnerability is handled as CVE-2021-26734. It is possible to launch the attack on the local host. There is not any exploit available. Upgrading the affected component is advised.

Detailsinfo

A vulnerability has been found in Zscaler Client Connector Installer on Windows and classified as problematic. This vulnerability affects an unknown function of the component Uninstallation Handler. The manipulation with an unknown input leads to a privileges management vulnerability. The CWE definition for the vulnerability is CWE-269. The product does not properly assign, modify, track, or check privileges for an actor, creating an unintended sphere of control for that actor. As an impact it is known to affect availability. CVE summarizes:

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.

The weakness was released 10/23/2023. The advisory is available at help.zscaler.com. This vulnerability was named CVE-2021-26734 since 02/05/2021. The technical details are unknown and an exploit is not available. This vulnerability is assigned to T1068 by the MITRE ATT&CK project.

Upgrading to version 3.4.0.124 eliminates this vulnerability.

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Productinfo

Vendor

Zscaler

Name

Client Connector Installer

CPE 2.3info

🔍

CPE 2.2info

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CVSSv4info

VulDB Vector: 🔍
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 4.1
VulDB Meta Temp Score: 4.1

VulDB Base Score: 2.5
VulDB Temp Score: 2.4
VulDB Vector: 🔍
VulDB Reliability: 🔍

NVD Base Score: 5.5
NVD Vector: 🔍

CNA Base Score: 4.4
CNA Vector (Zscaler, Inc.): 🔍

CVSSv2info

AV	AC	Au	C	I	A
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Vector	Complexity	Authentication	Confidentiality	Integrity	Availability
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VulDB Base Score: 🔍
VulDB Temp Score: 🔍
VulDB Reliability: 🔍

Exploitinginfo

Class: Privileges management
CWE: CWE-269 / CWE-266
CAPEC: 🔍
ATT&CK: 🔍

Physical: Partially
Local: Yes
Remote: Partially

Availability: 🔍
Status: Not defined

EPSS Score: 🔍
EPSS Percentile: 🔍

Price Prediction: 🔍
Current Price Estimation: 🔍

0-Day	Unlock	Unlock	Unlock	Unlock
Today	Unlock	Unlock	Unlock	Unlock

Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔍

Upgrade: Client Connector Installer 3.4.0.124

Timelineinfo

02/05/2021 🔍
10/23/2023 +989 days 🔍
10/23/2023 +0 days 🔍
11/12/2023 +20 days 🔍

Sourcesinfo

Advisory: help.zscaler.com
Status: Confirmed

CVE: CVE-2021-26734 (🔍)
GCVE (CVE): GCVE-0-2021-26734
GCVE (VulDB): GCVE-100-243166

Entryinfo

Created: 10/23/2023 16:50
Updated: 11/12/2023 18:14
Changes: 10/23/2023 16:50 (50), 11/12/2023 18:14 (11)
Complete: 🔍
Cache ID: 216::103