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TI-2021-08412 Aliases CVE-2021-26734GHSA-r4fj-mm48-prvv

Junction Delete leading to elevation of privilege

Priority LOW 24CWE-269Published · Updated

Key facts

Attack vector
Local
Privileges required
None
User interaction
Required
Attack complexity
Low
Impact type
Privilege escalation
Confidentiality · integrity · availability
None · High · None
Fix status
Fixed

Attack profile from CVSS 3.1 · NVD. Fix status from CNA. Impact type from CWE-269.

Summary

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.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.00154 4th percentileScored 2026-11-07
Fix Fixed Client Connector (Zscaler): 3.4.0.124

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
None
Automatable
No
Technical impact
Partial

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

VendorProductAffected versionsFixed inStatusSource
ZscalerClient Connectorbefore 3.4.0.1243.4.0.124Patch availableCNA
  • Client Connector VendorZscaler Affected before 3.4.0.124 Fixed in 3.4.0.124 Patch available CNA

CPE configurations NVD · 1

CPEVersionsRoleVendor
cpe:2.3:a:zscaler:client_connector:*:*:*:*:*:windows:*:*before 3.4.0.124VulnerableZscaler
  • cpe:2.3:a:zscaler:client_connector:*:*:*:*:*:windows:*:* Versions before 3.4.0.124 Vulnerable ·Zscaler

Remediation

  • Fix · CNA Client Connector (Zscaler) Fixed in 3.4.0.124

Timeline

  1. 2026-10-02 Threatist record created from CVE-2021-26734
  2. 2026-10-03 Alias added: GHSA-r4fj-mm48-prvv

References

Other 1

  • TI-2020-09334 The Zscaler Client Connector for Windows prior to 2.1.2.74 had a stack based buffer… CVSS 3.1CRITICAL 9.8
  • TI-2024-15528 Local Privilege Escalation via lack of input validation CVSS 3.1CRITICAL 9.8
  • TI-2024-15526 Insecure MacOS code sign check fallback CVSS 3.1CRITICAL 9.8
  • TI-2024-15505 Multiple Arbitrary Creates/Overwrites by link following CVSS 3.1CRITICAL 9.8
  • TI-2023-13308 Out-of-bounds write to heap in pacparser CVSS 3.1CRITICAL 9.8
  • TI-2023-13315 ZCC on Linux privilege escalation CVSS 3.1CRITICAL 9.8
See all 40 →

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences