{
  "document": {
    "acknowledgments": [
      {
        "names": [
          "Daniel dos Santos"
        ],
        "organization": "Forescout Technologies",
        "summary": "reporting these vulnerabilities to CISA"
      },
      {
        "organization": "Siemens",
        "summary": "reporting these vulnerabilities to CISA"
      }
    ],
    "category": "csaf_security_advisory",
    "csaf_version": "2.0",
    "distribution": {
      "text": "Disclosure is not limited",
      "tlp": {
        "label": "WHITE",
        "url": "https://us-cert.cisa.gov/tlp/"
      }
    },
    "lang": "en-US",
    "notes": [
      {
        "category": "general",
        "text": "This CSAF advisory was extracted from unstructured data and may contain inaccuracies. If you notice any errors, please reach out to the designated contact at CISA CSAF: central@cisa.dhs.gov",
        "title": "CISA Disclaimer"
      },
      {
        "category": "legal_disclaimer",
        "text": "All information products included in https://us-cert.cisa.gov/ics are provided \"as is\" for informational purposes only. The Department of Homeland Security (DHS) does not provide any warranties of any kind regarding any information contained within. DHS does not endorse any commercial product or service, referenced in this product or otherwise. Further dissemination of this product is governed by the Traffic Light Protocol (TLP) marking in the header. For more information about TLP, see https://us-cert.cisa.gov/tlp/.",
        "title": "Legal Notice"
      },
      {
        "category": "summary",
        "text": "Successful exploitation of these vulnerabilities could allow a denial-of-service condition or for the execution of code remotely.",
        "title": "Risk evaluation"
      },
      {
        "category": "other",
        "text": "Multiple Sectors",
        "title": "Critical infrastructure sectors"
      },
      {
        "category": "other",
        "text": "Worldwide",
        "title": "Countries/areas deployed"
      },
      {
        "category": "other",
        "text": "Germany",
        "title": "Company headquarters location"
      },
      {
        "category": "general",
        "text": "CISA recommends users take defensive measures to minimize the risk of exploitation of these vulnerabilities. Specifically, users should:",
        "title": "Recommended Practices"
      },
      {
        "category": "general",
        "text": "CISA reminds organizations to perform proper impact analysis and risk assessment prior to deploying defensive measures.\nCISA also provides a section for control systems security recommended practices on the ICS webpage onus-cert.cisa.gov. Several recommended practices are available for reading and download, including Improving Industrial Control Systems Cybersecurity with Defense-in-Depth Strategies.",
        "title": "Recommended Practices"
      },
      {
        "category": "general",
        "text": "Additional mitigation guidance and recommended practices are publicly available on the ICS webpage on us-cert.cisa.gov in the Technical Information Paper, ICS-TIP-12-146-01B--Targeted Cyber Intrusion Detection and Mitigation Strategies.\nOrganizations observing any suspected malicious activity should follow their established internal procedures and report their findings to CISA for tracking and correlation against other incidents.",
        "title": "Recommended Practices"
      },
      {
        "category": "general",
        "text": "For further inquiries on security vulnerabilities in Siemens products and solutions, please contact the Siemens ProductCERT: https://www.siemens.com/cert/advisories",
        "title": "Additional Resources"
      },
      {
        "category": "other",
        "text": "No known public exploits specifically target these vulnerabilities.",
        "title": "Exploitability"
      }
    ],
    "publisher": {
      "category": "coordinator",
      "contact_details": "Email: CISAservicedesk@cisa.dhs.gov;\n Toll Free: 1-888-282-0870",
      "name": "CISA",
      "namespace": "https://www.cisa.gov/"
    },
    "references": [
      {
        "category": "external",
        "summary": "SSA-185699: Out of Bounds Write Vulnerabilities (NAME:WRECK) in the DNS Module of Nucleus RTOS - CSAF Version",
        "url": "https://cert-portal.siemens.com/productcert/csaf/ssa-185699.json"
      },
      {
        "category": "self",
        "summary": "ICS Advisory ICSA-21-103-04 JSON",
        "url": "https://raw.githubusercontent.com/cisagov/CSAF/develop/csaf_files/OT/white/2021/icsa-21-103-04.json"
      },
      {
        "category": "self",
        "summary": "ICS Advisory ICSA-21-103-04 Web Version",
        "url": "https://www.cisa.gov/news-events/ics-advisories/icsa-21-103-04"
      },
      {
        "category": "external",
        "summary": "Recommended Practices",
        "url": "https://us-cert.cisa.gov/ics/alerts/ICS-ALERT-10-301-01"
      },
      {
        "category": "external",
        "summary": "Recommended Practices",
        "url": "https://us-cert.cisa.gov/sites/default/files/recommended_practices/NCCIC_ICS-CERT_Defense_in_Depth_2016_S508C.pdf"
      },
      {
        "category": "external",
        "summary": "Recommended Practices",
        "url": "https://us-cert.cisa.gov/ics/tips/ICS-TIP-12-146-01B"
      },
      {
        "category": "external",
        "summary": "SSA-185699: Out of Bounds Write Vulnerabilities (NAME:WRECK) in the DNS Module of Nucleus RTOS - PDF Version",
        "url": "https://cert-portal.siemens.com/productcert/pdf/ssa-185699.pdf"
      },
      {
        "category": "external",
        "summary": "SSA-185699: Out of Bounds Write Vulnerabilities (NAME:WRECK) in the DNS Module of Nucleus RTOS - TXT Version",
        "url": "https://cert-portal.siemens.com/productcert/txt/ssa-185699.txt"
      }
    ],
    "title": "Siemens Nucleus Products DNS Module (Update A)",
    "tracking": {
      "current_release_date": "2021-11-11T00:00:00.000000Z",
      "generator": {
        "engine": {
          "name": "CISA CSAF Generator",
          "version": "1.0.0"
        }
      },
      "id": "ICSA-21-103-04",
      "initial_release_date": "2021-04-13T00:00:00.000000Z",
      "revision_history": [
        {
          "date": "2021-04-13T00:00:00.000000Z",
          "legacy_version": "Initial",
          "number": "1",
          "summary": "ICSA-21-103-04 Siemens Nucleus Products DNS Module"
        },
        {
          "date": "2021-11-11T00:00:00.000000Z",
          "legacy_version": "A",
          "number": "2",
          "summary": "ICSA-21-103-04 Siemens Nucleus Products DNS Module (Update A)"
        }
      ],
      "status": "final",
      "version": "2"
    }
  },
  "product_tree": {
    "branches": [
      {
        "branches": [
          {
            "branches": [
              {
                "category": "product_version_range",
                "name": "\u003c V5.2",
                "product": {
                  "name": "Nucleus NET",
                  "product_id": "CSAFPID-0001"
                }
              }
            ],
            "category": "product_name",
            "name": "Nucleus NET"
          },
          {
            "branches": [
              {
                "category": "product_version_range",
                "name": "Versions including affected DNS modules",
                "product": {
                  "name": "Nucleus Source Code",
                  "product_id": "CSAFPID-0002"
                }
              }
            ],
            "category": "product_name",
            "name": "Nucleus Source Code"
          }
        ],
        "category": "vendor",
        "name": "Siemens"
      }
    ]
  },
  "vulnerabilities": [
    {
      "cve": "CVE-2020-15795",
      "cwe": {
        "id": "CWE-787",
        "name": "Out-of-bounds Write"
      },
      "notes": [
        {
          "category": "summary",
          "text": "The DNS domain name label parsing functionality does not properly validate the names in DNS-responses. The parsing of malformed responses could result in a write past the end of an allocated structure. An attacker with a privileged position in the network could leverage this vulnerability to execute code in the context of the current process or cause a denial-of-service condition.",
          "title": "Summary"
        }
      ],
      "product_status": {
        "known_affected": [
          "CSAFPID-0001",
          "CSAFPID-0002"
        ]
      },
      "references": [
        {
          "summary": "CVE-2020-15795 Mitre 5.0 json",
          "url": "https://cert-portal.siemens.com/productcert/mitre/CVE-2020-15795.json"
        },
        {
          "category": "external",
          "summary": "web.nvd.nist.gov",
          "url": "http://web.nvd.nist.gov/view/vuln/detail?vulnId=CVE-2020-15795"
        },
        {
          "category": "external",
          "summary": "www.first.org",
          "url": "https://www.first.org/cvss/calculator/3.0#CVSS:3.0/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H"
        }
      ],
      "remediations": [
        {
          "category": "mitigation",
          "details": "Update to the latest version of Nucleus ReadyStart V3 or V4",
          "product_ids": [
            "CSAFPID-0001"
          ]
        },
        {
          "category": "mitigation",
          "details": "Note that the latest version of Nucleus NET (V5.2) is not affected, but is already beyond end of software support",
          "product_ids": [
            "CSAFPID-0001"
          ]
        },
        {
          "category": "mitigation",
          "details": "Contact customer support or your local Nucleus Sales team for mitigation advice",
          "product_ids": [
            "CSAFPID-0001"
          ]
        },
        {
          "category": "no_fix_planned",
          "details": "Currently no remediation is planned",
          "product_ids": [
            "CSAFPID-0001"
          ]
        },
        {
          "category": "vendor_fix",
          "details": "Contact customer support to receive patch and update information",
          "product_ids": [
            "CSAFPID-0002"
          ]
        },
        {
          "category": "workaround",
          "details": "Avoid using DNS client of affected versions",
          "product_ids": [
            "CSAFPID-0001",
            "CSAFPID-0002"
          ]
        },
        {
          "category": "mitigation",
          "details": "As a general security measure, Siemens strongly recommends to protect network access to devices with appropriate mechanisms. In order to operate the devices in a protected IT environment, Siemens recommends to configure the environment according to Siemens\u0027 operational guidelines for Industrial Security (Download: https://www.siemens.com/cert/operational-guidelines-industrial-security), and to follow the recommendations in the product manuals.\n\nAdditional information on Industrial Security by Siemens can be found at: https://www.siemens.com/industrialsecurity",
          "product_ids": [
            "CSAFPID-0001",
            "CSAFPID-0002"
          ]
        }
      ],
      "scores": [
        {
          "cvss_v3": {
            "baseScore": 8.1,
            "baseSeverity": "HIGH",
            "vectorString": "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H/E:P/RL:O/RC:C",
            "version": "3.1"
          },
          "products": [
            "CSAFPID-0001",
            "CSAFPID-0002"
          ]
        }
      ],
      "title": "CVE-2020-15795"
    },
    {
      "cve": "CVE-2020-27009",
      "cwe": {
        "id": "CWE-823",
        "name": "Use of Out-of-range Pointer Offset"
      },
      "notes": [
        {
          "category": "summary",
          "text": "The DNS domain name record decompression functionality does not properly validate the pointer offset values. The parsing of malformed responses could result in a write past the end of an allocated structure. An attacker with a privileged position in the network could leverage this vulnerability to execute code in the context of the current process or cause a denial-of-service condition.",
          "title": "Summary"
        }
      ],
      "product_status": {
        "known_affected": [
          "CSAFPID-0001",
          "CSAFPID-0002"
        ]
      },
      "references": [
        {
          "summary": "CVE-2020-27009 Mitre 5.0 json",
          "url": "https://cert-portal.siemens.com/productcert/mitre/CVE-2020-27009.json"
        },
        {
          "category": "external",
          "summary": "web.nvd.nist.gov",
          "url": "http://web.nvd.nist.gov/view/vuln/detail?vulnId=CVE-2020-27009"
        },
        {
          "category": "external",
          "summary": "www.first.org",
          "url": "https://www.first.org/cvss/calculator/3.0#CVSS:3.0/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H"
        }
      ],
      "remediations": [
        {
          "category": "mitigation",
          "details": "Update to the latest version of Nucleus ReadyStart V3 or V4",
          "product_ids": [
            "CSAFPID-0001"
          ]
        },
        {
          "category": "mitigation",
          "details": "Note that the latest version of Nucleus NET (V5.2) is not affected, but is already beyond end of software support",
          "product_ids": [
            "CSAFPID-0001"
          ]
        },
        {
          "category": "mitigation",
          "details": "Contact customer support or your local Nucleus Sales team for mitigation advice",
          "product_ids": [
            "CSAFPID-0001"
          ]
        },
        {
          "category": "no_fix_planned",
          "details": "Currently no remediation is planned",
          "product_ids": [
            "CSAFPID-0001"
          ]
        },
        {
          "category": "vendor_fix",
          "details": "Contact customer support to receive patch and update information",
          "product_ids": [
            "CSAFPID-0002"
          ]
        },
        {
          "category": "workaround",
          "details": "Avoid using DNS client of affected versions",
          "product_ids": [
            "CSAFPID-0001",
            "CSAFPID-0002"
          ]
        },
        {
          "category": "mitigation",
          "details": "As a general security measure, Siemens strongly recommends to protect network access to devices with appropriate mechanisms. In order to operate the devices in a protected IT environment, Siemens recommends to configure the environment according to Siemens\u0027 operational guidelines for Industrial Security (Download: https://www.siemens.com/cert/operational-guidelines-industrial-security), and to follow the recommendations in the product manuals.\n\nAdditional information on Industrial Security by Siemens can be found at: https://www.siemens.com/industrialsecurity",
          "product_ids": [
            "CSAFPID-0001",
            "CSAFPID-0002"
          ]
        }
      ],
      "scores": [
        {
          "cvss_v3": {
            "baseScore": 8.1,
            "baseSeverity": "HIGH",
            "vectorString": "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H/E:P/RL:O/RC:C",
            "version": "3.1"
          },
          "products": [
            "CSAFPID-0001",
            "CSAFPID-0002"
          ]
        }
      ],
      "title": "CVE-2020-27009"
    }
  ]
}