Vulnerability-Lookup

CVE-2026-59564 (GCVE-0-2026-59564)

Vulnerability from cvelistv5 – Published: 2026-08-24 13:39 – Updated: 2026-08-25 03:56

Title

Authentication bypass between ZCC and client connector portal

Summary

An authentication bypass issue exists in communications between affected versions of the Zscaler Client Connector and the Zscaler Client Connector Portal.

Severity

9.1 (Critical)


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

SSVC

Exploitation: none Automatable: yes Technical Impact: total

CISA Coordinator · CISA-ADP (v2.0.3)

Decision recorded 2026-08-24 00:00 UTC

CWE

CWE-304 - Missing critical step in authentication

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 , < Windows: 4.6.0.457, 4.7.0.317, 4.8.0.232, 4.9.0.372 (custom) Affected: 0 , < MacOS: 4.5.2.312, 4.7.0.292, 4.8.0.191 (custom) Affected: 0 , < iOS: 4.5.1 (custom) Affected: 0 , < Android: 4.2 (custom) Affected: 0 , < ChromeOS: 4.2 (custom) Affected: 0 , < Linux: 3.7.2.64, 4.2.1.64 (custom)	guessed

Date Public

2026-08-21 09:48

Show details on NVD website

JSON

To clipboard

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FKIE_CVE-2026-59564

Vulnerability from fkie_nvd - Published: 2026-08-24 14:16 - Updated: 2026-08-25 04:18

Severity

9.1 (Critical) - CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N

Summary

An authentication bypass issue exists in communications between affected versions of the Zscaler Client Connector and the Zscaler Client Connector Portal.

References

	URL	Tags
	cve@zscaler.com	https://help.zscaler.com/zscaler-client-connector/client-connector-app-release-summary-2026

Impacted products

	Vendor	Product	Version

JSON

To clipboard

{
  "affected": [
    {
      "affectedData": [
        {
          "defaultStatus": "affected",
          "platforms": [
            "Windows",
            "MacOS",
            "Linux",
            "iOS",
            "Android"
          ],
          "product": "Client Connector",
          "vendor": "Zscaler",
          "versions": [
            {
              "lessThan": "Windows: 4.6.0.457, 4.7.0.317, 4.8.0.232, 4.9.0.372",
              "status": "affected",
              "version": "0",
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            },
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            },
            {
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              "status": "affected",
              "version": "0",
              "versionType": "custom"
            }
          ]
        }
      ],
      "source": "cve@zscaler.com"
    }
  ],
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "An authentication bypass issue exists in communications between affected versions of the Zscaler Client Connector and the Zscaler Client Connector Portal."
    }
  ],
  "id": "CVE-2026-59564",
  "lastModified": "2026-08-25T04:18:13.210",
  "metrics": {
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        "cvssData": {
          "attackComplexity": "LOW",
          "attackVector": "NETWORK",
          "availabilityImpact": "NONE",
          "baseScore": 9.1,
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GHSA-R7WR-WRCM-FJ8Q

Vulnerability from github – Published: 2026-08-24 15:31 – Updated: 2026-08-24 15:31

Details

An authentication bypass issue exists in communications between affected versions of the Zscaler Client Connector and the Zscaler Client Connector Portal.

Severity

9.1 (Critical)


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

Show details on source website

JSON

To clipboard

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  "affected": [],
  "aliases": [
    "CVE-2026-59564"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-304"
    ],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2026-08-24T14:16:55Z",
    "severity": "CRITICAL"
  },
  "details": "An authentication bypass issue exists in communications between affected versions of the Zscaler Client Connector and the Zscaler Client Connector Portal.",
  "id": "GHSA-r7wr-wrcm-fj8q",
  "modified": "2026-08-24T15:31:51Z",
  "published": "2026-08-24T15:31:51Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-59564"
    },
    {
      "type": "WEB",
      "url": "https://help.zscaler.com/zscaler-client-connector/client-connector-app-release-summary-2026"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N",
      "type": "CVSS_V3"
    }
  ]
}

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.

Action not permitted

CVE-2026-59564 (GCVE-0-2026-59564)

FKIE_CVE-2026-59564

GHSA-R7WR-WRCM-FJ8Q

Tags

Sightings

Nomenclature