Vulnerability-Lookup

NN-2026:14-01

Vulnerability from csaf_nozominetworks - Published: 2026-08-11 11:00 - Updated: 2026-08-11 11:00

Summary

Npcap driver installed without administrator-only access restriction on Windows in Arc before v2.7.0

Severity

Medium

Notes

Risk Level for Nozomi customers: Medium

CVE-2026-33921

5.2 (Medium)


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

CWE-1188 - Initialization of a Resource with an Insecure Default

Affected products

Fixed 1 product

Product	Identifier	Version	Remediation
Nozomi Networks Arc 2.7.0 Nozomi Networks / Arc		2.7.0

Known affected 1 product

Product	Identifier	Version	Remediation
Nozomi Networks Arc <2.7.0 Nozomi Networks / Arc		vers:gem/<2.7.0	Mitigation Vendor Fix

Threats

Impact A local user without administrative privileges could use the Npcap driver to capture the traffic reaching the host, which discloses information belonging both to the host and to other systems on the same network segment, and to send arbitrary raw packets on that segment.

References

3 references

URL	Category
https://cve.mitre.org/cgi-bin/cvename.cgi?name=CV…	external
https://security.nozominetworks.com/csaf/2026/nn-…	self
https://security.nozominetworks.com/NN-2026:14-01	self

Acknowledgments

Nozomi Networks Stefano Balzarotti

JSON

To clipboard

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    "notes": [
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        "title": "Risk Level for Nozomi customers"
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                "category": "product_version_range",
                "name": "vers:gem/\u003c2.7.0",
                "product": {
                  "name": "Nozomi Networks Arc \u003c2.7.0",
                  "product_id": "CSAFPID-0001"
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          "text": "The Windows installer deployed Npcap leaving its access restriction option at the insecure default value, so the driver was accessible to every local user of the host instead of being restricted to administrators only.",
          "title": "Vulnerability summary"
        }
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      "product_status": {
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          "url": "https://security.nozominetworks.com/csaf/2026/nn-2026_14-01.json"
        },
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          "category": "self",
          "summary": "Human-readable advisory.",
          "url": "https://security.nozominetworks.com/NN-2026:14-01"
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      "remediations": [
        {
          "category": "mitigation",
          "details": "Reinstall Npcap on the affected host with the \"Restrict Npcap driver\u0027s access to Administrators only\" option enabled.",
          "product_ids": [
            "CSAFPID-0001"
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        },
        {
          "category": "vendor_fix",
          "details": "Upgrade Arc to v2.7.0 or later.",
          "product_ids": [
            "CSAFPID-0001"
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        }
      ],
      "scores": [
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            "baseScore": 5.2,
            "baseSeverity": "MEDIUM",
            "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:L/I:L/A:N",
            "version": "3.1"
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          "details": "A local user without administrative privileges could use the Npcap driver to capture the traffic reaching the host, which discloses information belonging both to the host and to other systems on the same network segment, and to send arbitrary raw packets on that segment."
        }
      ],
      "title": "Npcap driver installed without administrator-only access restriction on Windows in Arc before v2.7.0"
    }
  ]
}

CVE-2026-33921 (GCVE-0-2026-33921)

Vulnerability from cvelistv5 – Published: 2026-08-11 09:48 – Updated: 2026-08-11 14:15

Title

Npcap driver installed without administrator-only access restriction on Windows in Arc before v2.7.0

Summary

The Windows installer deployed Npcap leaving its access restriction option at the insecure default value, so the driver was accessible to every local user of the host instead of being restricted to administrators only. A local user without administrative privileges could use the Npcap driver to capture the traffic reaching the host, which discloses information belonging both to the host and to other systems on the same network segment, and to send arbitrary raw packets on that segment.

Severity

4.8 (Medium)


                        
                          CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:L/VI:L/VA:N/SC:L/SI:L/SA:N

5.2 (Medium)


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

SSVC

Exploitation: none Automatable: no Technical Impact: partial

CISA Coordinator (v2.0.3)

CWE

CWE-1188 - Initialization of a resource with an insecure default

Assigner

Nozomi

References

1 reference

URL	Tags
https://security.nozominetworks.com/NN-2026:14-01

Impacted products

1 product

Vendor	Product	Version
Nozomi Networks	Arc	Affected: 0 , < 2.7.0 (semver)

Date Public

2026-08-11 07:00

Credits

This issue was found by Stefano Balzarotti of Nozomi Networks during an internal investigation.

Show details on NVD website

JSON

To clipboard

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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.

Action not permitted

NN-2026:14-01

CVE-2026-33921 (GCVE-0-2026-33921)

Tags

Sightings

Nomenclature