Vulnerability-Lookup

CVE-2026-25687 (GCVE-0-2026-25687)

Vulnerability from cvelistv5 – Published: 2026-09-14 14:37 – Updated: 2026-09-14 15:41

Title

ZCC race condition in ZPA tunnel handler

Summary

A race condition in the ZPA tunnel handler of affected versions of Zscaler Client Connector (ZCC) allows a heap corruption, resulting in a denial of service (client crash) and potentially arbitrary code execution in the context of the ZCC process.

Severity

8.1 (High)


                        
                          CVSS:3.1/AV:N/AC:H/PR:N/UI:N/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 2026-09-14 15:33 UTC

CWE

CWE-366 - Race condition within a thread

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: 4.6 , < 4.6.0.486 (custom) Affected: 4.7 , < 4.7.0.350 (custom) Affected: 4.8 , < 4.8.0.267 (custom) Affected: 4.9 , < 4.9.0.412 (custom)	guessed

Date Public

2026-09-14 14:36

Credits

GovTech Singapore Red Team

Show details on NVD website

JSON

To clipboard

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FKIE_CVE-2026-25687

Vulnerability from fkie_nvd - Published: 2026-09-14 15:17 - Updated: 2026-09-14 16:17

Severity

8.1 (High) - CVSS:3.1/AV:N/AC:H/PR:N/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-2026

Impacted products

	Vendor	Product	Version

JSON

To clipboard

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    {
      "affectedData": [
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          "defaultStatus": "unaffected",
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          ],
          "product": "Client Connector",
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GHSA-4WWC-HGC4-J27V

Vulnerability from github – Published: 2026-09-14 15:32 – Updated: 2026-09-14 15:32

Details

Severity

8.1 (High)


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

Show details on source website

JSON

To clipboard

{
  "affected": [],
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    "CVE-2026-25687"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-366"
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    "github_reviewed_at": null,
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  },
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  "id": "GHSA-4wwc-hgc4-j27v",
  "modified": "2026-09-14T15:32:48Z",
  "published": "2026-09-14T15:32:48Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-25687"
    },
    {
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      "score": "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H",
      "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-2026-25687 (GCVE-0-2026-25687)

FKIE_CVE-2026-25687

GHSA-4WWC-HGC4-J27V

Tags

Sightings

Nomenclature