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
Product Identifier Version Remediation
Nozomi Networks Arc 2.7.0
Nozomi Networks / Arc
 2.7.0
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
Acknowledgments
Nozomi Networks Stefano Balzarotti
To clipboard 

{
  "document": {
    "aggregate_severity": {
      "text": "MEDIUM"
    },
    "category": "csaf_vex",
    "csaf_version": "2.0",
    "distribution": {
      "tlp": {
        "label": "WHITE"
      }
    },
    "lang": "en-US",
    "notes": [
      {
        "category": "other",
        "text": "Medium",
        "title": "Risk Level for Nozomi customers"
      }
    ],
    "publisher": {
      "category": "vendor",
      "contact_details": "Nozomi Networks Product Security team can be reached at prodsec@nozominetworks.com",
      "name": "Nozomi Networks Product Security",
      "namespace": "https://security.nozominetworks.com/psirt"
    },
    "title": "Npcap driver installed without administrator-only access restriction on Windows in Arc before v2.7.0",
    "tracking": {
      "aliases": [
        "CVE-2026-33921"
      ],
      "current_release_date": "2026-08-11T11:00:00.000Z",
      "id": "NN-2026:14-01",
      "initial_release_date": "2026-08-11T11:00:00.000Z",
      "revision_history": [
        {
          "date": "2026-08-11T11:00:00.000Z",
          "number": "1",
          "summary": "Initial revision"
        }
      ],
      "status": "final",
      "version": "1"
    }
  },
  "product_tree": {
    "branches": [
      {
        "branches": [
          {
            "branches": [
              {
                "category": "product_version_range",
                "name": "vers:gem/\u003c2.7.0",
                "product": {
                  "name": "Nozomi Networks Arc \u003c2.7.0",
                  "product_id": "CSAFPID-0001"
                }
              },
              {
                "category": "product_version",
                "name": "2.7.0",
                "product": {
                  "name": "Nozomi Networks Arc 2.7.0",
                  "product_id": "CSAFPID-0002"
                }
              }
            ],
            "category": "product_name",
            "name": "Arc"
          }
        ],
        "category": "vendor",
        "name": "Nozomi Networks"
      }
    ]
  },
  "vulnerabilities": [
    {
      "acknowledgments": [
        {
          "names": [
            "Stefano Balzarotti"
          ],
          "organization": "Nozomi Networks",
          "summary": "finding this issue during an internal investigation"
        }
      ],
      "cve": "CVE-2026-33921",
      "cwe": {
        "id": "CWE-1188",
        "name": "Initialization of a Resource with an Insecure Default"
      },
      "discovery_date": "2026-08-11T11:00:00.000Z",
      "ids": [
        {
          "system_name": "Nozomi Networks Security Advisory ID",
          "text": "NN-2026:14-01"
        }
      ],
      "notes": [
        {
          "category": "summary",
          "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"
        }
      ],
      "product_status": {
        "fixed": [
          "CSAFPID-0002"
        ],
        "known_affected": [
          "CSAFPID-0001"
        ]
      },
      "references": [
        {
          "category": "external",
          "summary": "Mitre CVE entry",
          "url": "https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2026-33921"
        },
        {
          "category": "self",
          "summary": "Canonical URL",
          "url": "https://security.nozominetworks.com/csaf/2026/nn-2026_14-01.json"
        },
        {
          "category": "self",
          "summary": "Human-readable advisory.",
          "url": "https://security.nozominetworks.com/NN-2026:14-01"
        }
      ],
      "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"
          ]
        },
        {
          "category": "vendor_fix",
          "details": "Upgrade Arc to v2.7.0 or later.",
          "product_ids": [
            "CSAFPID-0001"
          ]
        }
      ],
      "scores": [
        {
          "cvss_v3": {
            "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"
          },
          "products": [
            "CSAFPID-0001"
          ]
        }
      ],
      "threats": [
        {
          "category": "impact",
          "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"
    }
  ]
}



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