NN-2026:20-01

Vulnerability from csaf_nozominetworks - Published: 2026-09-08 11:00 - Updated: 2026-09-08 11:00
Summary
Disabled and non-configurable certificate/host key validation in Smart Polling in Guardian/CMC before 26.3.0 and Arc before v2.7.0
Severity
High
Notes
Risk Level for Nozomi customers: High
CVE-2026-33389
7.5 (High)
CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:C/C:H/I:L/A:L
CWE-671 - Lack of Administrator Control over Security
Affected products
Product Identifier Version Remediation
Nozomi Networks Guardian 26.3.0
Nozomi Networks / Guardian
 26.3.0
Nozomi Networks CMC 26.3.0
Nozomi Networks / CMC
 26.3.0
Nozomi Networks Arc 2.7.0
Nozomi Networks / Arc
 2.7.0
Product Identifier Version Remediation
Nozomi Networks Guardian <26.3.0
Nozomi Networks / Guardian
 vers:gem/<26.3.0
Mitigation
Vendor Fix
Nozomi Networks CMC <26.3.0
Nozomi Networks / CMC
 vers:gem/<26.3.0
Mitigation
Vendor Fix
Nozomi Networks Arc <2.7.0
Nozomi Networks / Arc
 vers:gem/<2.7.0
Mitigation
Vendor Fix
Threats
Impact A man-in-the-middle attacker positioned between a sensor and a polled device can, during a polling session, impersonate the device and intercept the communication, including the credentials used to access it. The captured credentials can then be replayed to authenticate against the device itself or against other devices sharing the same credentials, allowing the attacker to access and tamper with the device's data and to disrupt its operations.
References
Acknowledgments
Nozomi Networks Stefano Balzarotti
Nozomi Networks Product Security team Andrea Palanca
To clipboard 

{
  "document": {
    "aggregate_severity": {
      "text": "HIGH"
    },
    "category": "csaf_vex",
    "csaf_version": "2.0",
    "distribution": {
      "tlp": {
        "label": "WHITE"
      }
    },
    "lang": "en-US",
    "notes": [
      {
        "category": "other",
        "text": "High",
        "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": "Disabled and non-configurable certificate/host key validation in Smart Polling in Guardian/CMC before 26.3.0 and Arc before v2.7.0",
    "tracking": {
      "aliases": [
        "CVE-2026-33389"
      ],
      "current_release_date": "2026-09-08T11:00:00.000Z",
      "id": "NN-2026:20-01",
      "initial_release_date": "2026-09-08T11:00:00.000Z",
      "revision_history": [
        {
          "date": "2026-09-08T11:00:00.000Z",
          "number": "1",
          "summary": "Initial revision"
        }
      ],
      "status": "final",
      "version": "1"
    }
  },
  "product_tree": {
    "branches": [
      {
        "branches": [
          {
            "branches": [
              {
                "category": "product_version_range",
                "name": "vers:gem/\u003c26.3.0",
                "product": {
                  "name": "Nozomi Networks Guardian \u003c26.3.0",
                  "product_id": "CSAFPID-0001"
                }
              },
              {
                "category": "product_version",
                "name": "26.3.0",
                "product": {
                  "name": "Nozomi Networks Guardian 26.3.0",
                  "product_id": "CSAFPID-0002"
                }
              }
            ],
            "category": "product_name",
            "name": "Guardian"
          },
          {
            "branches": [
              {
                "category": "product_version_range",
                "name": "vers:gem/\u003c26.3.0",
                "product": {
                  "name": "Nozomi Networks CMC \u003c26.3.0",
                  "product_id": "CSAFPID-0003"
                }
              },
              {
                "category": "product_version",
                "name": "26.3.0",
                "product": {
                  "name": "Nozomi Networks CMC 26.3.0",
                  "product_id": "CSAFPID-0004"
                }
              }
            ],
            "category": "product_name",
            "name": "CMC"
          },
          {
            "branches": [
              {
                "category": "product_version_range",
                "name": "vers:gem/\u003c2.7.0",
                "product": {
                  "name": "Nozomi Networks Arc \u003c2.7.0",
                  "product_id": "CSAFPID-0005"
                }
              },
              {
                "category": "product_version",
                "name": "2.7.0",
                "product": {
                  "name": "Nozomi Networks Arc 2.7.0",
                  "product_id": "CSAFPID-0006"
                }
              }
            ],
            "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"
        },
        {
          "names": [
            "Andrea Palanca"
          ],
          "organization": "Nozomi Networks Product Security team",
          "summary": "finding this issue during an internal investigation"
        }
      ],
      "cve": "CVE-2026-33389",
      "cwe": {
        "id": "CWE-671",
        "name": "Lack of Administrator Control over Security"
      },
      "discovery_date": "2026-09-08T11:00:00.000Z",
      "ids": [
        {
          "system_name": "Nozomi Networks Security Advisory ID",
          "text": "NN-2026:20-01"
        }
      ],
      "notes": [
        {
          "category": "summary",
          "text": "An improper certificate/host key validation vulnerability was discovered in the Smart Polling functionality, which established encrypted connections to target devices without validating the remote host\u0027s identity, and no option was provided to enable it.",
          "title": "Vulnerability summary"
        }
      ],
      "product_status": {
        "fixed": [
          "CSAFPID-0002",
          "CSAFPID-0004",
          "CSAFPID-0006"
        ],
        "known_affected": [
          "CSAFPID-0001",
          "CSAFPID-0003",
          "CSAFPID-0005"
        ]
      },
      "references": [
        {
          "category": "external",
          "summary": "Mitre CVE entry",
          "url": "https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2026-33389"
        },
        {
          "category": "self",
          "summary": "Canonical URL",
          "url": "https://security.nozominetworks.com/csaf/2026/nn-2026_20-01.json"
        },
        {
          "category": "self",
          "summary": "Human-readable advisory.",
          "url": "https://security.nozominetworks.com/NN-2026:20-01"
        }
      ],
      "remediations": [
        {
          "category": "mitigation",
          "details": "N/A",
          "product_ids": [
            "CSAFPID-0001",
            "CSAFPID-0003",
            "CSAFPID-0005"
          ]
        },
        {
          "category": "vendor_fix",
          "details": "Upgrade Guardian/CMC to v26.3.0 or later. Upgrade Arc to v2.7.0 or later.",
          "product_ids": [
            "CSAFPID-0001",
            "CSAFPID-0003",
            "CSAFPID-0005"
          ]
        }
      ],
      "scores": [
        {
          "cvss_v3": {
            "baseScore": 7.5,
            "baseSeverity": "HIGH",
            "vectorString": "CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:C/C:H/I:L/A:L",
            "version": "3.1"
          },
          "products": [
            "CSAFPID-0001",
            "CSAFPID-0003",
            "CSAFPID-0005"
          ]
        }
      ],
      "threats": [
        {
          "category": "impact",
          "details": "A man-in-the-middle attacker positioned between a sensor and a polled device can, during a polling session, impersonate the device and intercept the communication, including the credentials used to access it. The captured credentials can then be replayed to authenticate against the device itself or against other devices sharing the same credentials, allowing the attacker to access and tamper with the device\u0027s data and to disrupt its operations."
        }
      ],
      "title": "Disabled and non-configurable certificate/host key validation in Smart Polling in Guardian/CMC before 26.3.0 and Arc before v2.7.0"
    }
  ]
}



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