Vulnerability-Lookup

CVE-2021-26736 (GCVE-0-2021-26736)

Vulnerability from cvelistv5 – Published: 2023-10-23 13:21 – Updated: 2025-02-27 20:40

Title

ZApp Installer Privilege Escalation Vulnerabilities

Summary

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.

Severity

6.7 (Medium)


                        
                          CVSS:3.1/AV:L/AC:H/PR:L/UI:R/S:U/C:H/I:H/A:H

SSVC

Exploitation: none Automatable: no Technical Impact: total

CISA Coordinator · CISA-ADP (v2.0.3)

Decision recorded 2025-02-26 21:49 UTC

CWE

CWE-20 - Improper Input Validation

Assigner

Zscaler mitre root

References

1 reference

URL	Tags
https://help.zscaler.com/zscaler-client-connector…

Impacted products

1 product

Vendor	Product	Version	CPE status
Zscaler	Client Connector	Affected: 0 , < 3.6 (custom)	guessed

Credits

LMCO Red Team

Show details on NVD website

JSON

To clipboard

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FKIE_CVE-2021-26736

Vulnerability from fkie_nvd - Published: 2023-10-23 14:15 - Updated: 2026-06-17 03:43

Severity

6.7 (Medium) - CVSS:3.1/AV:L/AC:H/PR:L/UI:R/S:U/C:H/I:H/A:H
7.8 (High) - CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

Summary

References

	URL	Tags
	cve@zscaler.com	https://help.zscaler.com/zscaler-client-connector/client-connector-app-release-summary-2021	Release Notes
	af854a3a-2127-422b-91ae-364da2661108	https://help.zscaler.com/zscaler-client-connector/client-connector-app-release-summary-2021	Release Notes

Impacted products

	Vendor	Product	Version
	zscaler	client_connector	*

JSON

To clipboard

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}

GHSA-CMFG-V75G-8WM3

Vulnerability from github – Published: 2023-10-23 15:30 – Updated: 2024-04-04 08:52

Details

Severity

6.7 (Medium)


                  
                    CVSS:3.1/AV:L/AC:H/PR:L/UI:R/S:U/C:H/I:H/A:H

Show details on source website

JSON

To clipboard

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    "github_reviewed_at": null,
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    "severity": "HIGH"
  },
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  "id": "GHSA-cmfg-v75g-8wm3",
  "modified": "2024-04-04T08:52:58Z",
  "published": "2023-10-23T15:30:24Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2021-26736"
    },
    {
      "type": "WEB",
      "url": "https://help.zscaler.com/zscaler-client-connector/client-connector-app-release-summary-2021"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:L/AC:H/PR:L/UI:R/S:U/C:H/I:H/A:H",
      "type": "CVSS_V3"
    }
  ]
}

GSD-2021-26736

Vulnerability from gsd - Updated: 2023-12-13 01:23

Details

Aliases

CVE-2021-26736

Aliases

CVE-2021-26736

JSON

To clipboard

{
  "GSD": {
    "alias": "CVE-2021-26736",
    "id": "GSD-2021-26736"
  },
  "gsd": {
    "metadata": {
      "exploitCode": "unknown",
      "remediation": "unknown",
      "reportConfidence": "confirmed",
      "type": "vulnerability"
    },
    "osvSchema": {
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        "CVE-2021-26736"
      ],
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      "id": "GSD-2021-26736",
      "modified": "2023-12-13T01:23:33.951019Z",
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    }
  },
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}

WID-SEC-W-2023-2733

Vulnerability from csaf_certbund - Published: 2023-10-23 22:00 - Updated: 2023-10-23 22:00

Summary

ZScaler Client Connector: Mehrere Schwachstellen

Severity

Hoch

Scope

12 vulnerabilities in this advisory, including CVE-2021-26736.

CVE-2021-26736

Es besteht eine Schwachstelle in ZScaler Client Connector. Dieser Fehler besteht im Installer- und Uninstaller-Modul, da die Ausführung von Binärcode erlaubt ist. Ein lokaler Angreifer kann diese Schwachstelle ausnutzen, um Code mit SYSTEM-Rechten auszuführen. Eine erfolgreiche Ausnutzung erfordert eine Benutzerinteraktion.

Known affected: 1 product

Open the full advisory

Sightings

Author	Source	Type	Date	Other

Nomenclature

Seen: The vulnerability was mentioned, discussed, or observed by the user.
Confirmed: The vulnerability has been validated from an analyst's perspective.
Published Proof of Concept: A public proof of concept is available for this vulnerability.
Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
Not confirmed: The user expressed doubt about the validity of the vulnerability.
Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.

Detection rules are retrieved from Rulezet.

The MITRE ATT&CK techniques below are AI-generated suggestions, inferred from the description of the vulnerability by the CIRCL/vulnerability-attack-technique-classification-roberta-base model, served locally by ML-Gateway. They have not been verified by an analyst and are provided for guidance only.
The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.
Browse all ATT&CK techniques and the vulnerabilities related to each.

Related by attack behaviour

Vulnerabilities whose description is nearest to this one in the vector space of the CIRCL/vulnerability-attack-technique-biencoder model. This is a similarity search over the bi-encoder space (plain cosine), not a classification, and it has no measured accuracy.

Action not permitted

CVE-2021-26736 (GCVE-0-2021-26736)

FKIE_CVE-2021-26736

GHSA-CMFG-V75G-8WM3

GSD-2021-26736

WID-SEC-W-2023-2733

Tags

Sightings

Nomenclature

Related by attack behaviour