{
  "document": {
    "title": "SSA-705111: Multiple Vulnerabilities (NAME:WRECK) in the DNS Module of Nucleus RTOS",
    "category": "Siemens Security Advisory",
    "csaf_version": "2.0",
    "publisher": {
      "name": "Siemens ProductCERT",
      "contact_details": "productcert@siemens.com",
      "category": "vendor",
      "namespace": "https://www.siemens.com"
    },
    "distribution": {
      "text": "Disclosure is not limited.",
      "tlp": {
        "label": "WHITE"
      }
    },
    "tracking": {
      "id": "SSA-705111",
      "status": "final",
      "version": "3",
      "revision_history": [
        {
          "number": "1",
          "legacy_version": "1.0",
          "date": "2021-04-13T00:00:00Z",
          "summary": "Publication Date"
        },
        {
          "number": "2",
          "legacy_version": "1.1",
          "date": "2021-11-09T00:00:00Z",
          "summary": "Added solution for CVE-2021-25677 in Nucleus ReadyStart V3; consolidated list of products"
        },
        {
          "number": "3",
          "legacy_version": "1.2",
          "date": "2022-01-11T00:00:00Z",
          "summary": "Removed CAPITAL VSTAR as not affected"
        }
      ],
      "initial_release_date": "2021-04-13T00:00:00Z",
      "current_release_date": "2022-01-11T00:00:00Z",
      "generator": {
        "engine": {
          "name": "Siemens ProductCERT CSAF Generator",
          "version": "1"
        }
      }
    },
    "notes": [
      {
        "title": "Summary",
        "category": "summary",
        "text": "Security researchers discovered and disclosed 9 vulnerabilities in several DNS implementations, also known as “NAME:WRECK” vulnerabilities. The vulnerabilities described in this advisory are from this set.\n\nThe DNS client of affected products contains multiple vulnerabilities related to the handling of DNS responses and requests. The most severe could allow an attacker to manipulate the DNS responses and cause a denial-of-service condition.\n\nSiemens has released updates for several affected products and recommends to update to the latest versions. Siemens recommends specific countermeasures for products where updates are not available."
      },
      {
        "title": "General Recommendations",
        "category": "general",
        "text": "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' 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"
      },
      {
        "title": "Additional Resources",
        "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": "Terms of Use",
        "category": "legal_disclaimer",
        "text": "Siemens Security Advisories are subject to the terms and conditions contained in Siemens' underlying license terms or other applicable agreements previously agreed to with Siemens (hereinafter \"License Terms\"). To the extent applicable to information, software or documentation made available in or through a Siemens Security Advisory, the Terms of Use of Siemens' Global Website (https://www.siemens.com/terms_of_use, hereinafter \"Terms of Use\"), in particular Sections 8-10 of the Terms of Use, shall apply additionally. In case of conflicts, the License Terms shall prevail over the Terms of Use."
      }
    ],
    "references": [
      {
        "category": "self",
        "url": "https://cert-portal.siemens.com/productcert/pdf/ssa-705111.pdf",
        "summary": "SSA-705111: Multiple Vulnerabilities (NAME:WRECK) in the DNS Module of Nucleus RTOS - PDF Version"
      },
      {
        "category": "self",
        "url": "https://cert-portal.siemens.com/productcert/txt/ssa-705111.txt",
        "summary": "SSA-705111: Multiple Vulnerabilities (NAME:WRECK) in the DNS Module of Nucleus RTOS - TXT Version"
      },
      {
        "category": "self",
        "url": "https://cert-portal.siemens.com/productcert/csaf/ssa-705111.json",
        "summary": "SSA-705111: Multiple Vulnerabilities (NAME:WRECK) in the DNS Module of Nucleus RTOS - CSAF Version"
      }
    ],
    "acknowledgments": [
      {
        "names": [
          "Daniel dos Santos"
        ],
        "organization": "Forescout Technologies",
        "summary": "coordinated disclosure"
      }
    ]
  },
  "product_tree": {
    "branches": [
      {
        "name": "Siemens",
        "category": "vendor",
        "branches": [
          {
            "name": "Nucleus NET",
            "category": "product_name",
            "branches": [
              {
                "name": "vers:all/*",
                "category": "product_version_range",
                "product": {
                  "product_id": "1",
                  "name": "Nucleus NET"
                }
              }
            ]
          },
          {
            "name": "Nucleus ReadyStart V3",
            "category": "product_name",
            "branches": [
              {
                "name": "< V2017.02.3",
                "category": "product_version_range",
                "product": {
                  "product_id": "2",
                  "name": "Nucleus ReadyStart V3"
                }
              }
            ]
          },
          {
            "name": "Nucleus ReadyStart V3",
            "category": "product_name",
            "branches": [
              {
                "name": "< V2017.02.4",
                "category": "product_version_range",
                "product": {
                  "product_id": "3",
                  "name": "Nucleus ReadyStart V3"
                }
              }
            ]
          },
          {
            "name": "Nucleus ReadyStart V4",
            "category": "product_name",
            "branches": [
              {
                "name": "< V4.1.0",
                "category": "product_version_range",
                "product": {
                  "product_id": "4",
                  "name": "Nucleus ReadyStart V4"
                }
              }
            ]
          },
          {
            "name": "Nucleus Source Code",
            "category": "product_name",
            "branches": [
              {
                "name": "Versions including affected DNS modules",
                "category": "product_version_range",
                "product": {
                  "product_id": "5",
                  "name": "Nucleus Source Code"
                }
              }
            ]
          }
        ]
      }
    ]
  },
  "vulnerabilities": [
    {
      "title": "CVE-2020-27736",
      "notes": [
        {
          "title": "Summary",
          "category": "summary",
          "text": "The DNS domain name label parsing functionality does not properly validate the null-terminated name in DNS-responses. The parsing of malformed responses could result in a read past the end of an allocated structure. An attacker with a privileged position in the network could leverage this vulnerability to cause a denial-of-service condition or leak the read memory."
        }
      ],
      "cve": "CVE-2020-27736",
      "cwe": {
        "id": "CWE-170",
        "name": "Improper Null Termination"
      },
      "product_status": {
        "known_affected": [
          "1",
          "2",
          "4",
          "5"
        ]
      },
      "scores": [
        {
          "cvss_v3": {
            "version": "3.1",
            "baseScore": 6.5,
            "baseSeverity": "MEDIUM",
            "vectorString": "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:N/A:H/E:P/RL:O/RC:C"
          },
          "products": [
            "1",
            "2",
            "4",
            "5"
          ]
        }
      ],
      "remediations": [
        {
          "product_ids": [
            "1"
          ],
          "category": "mitigation",
          "details": "Update to the latest version of Nucleus ReadyStart V3 or V4"
        },
        {
          "product_ids": [
            "1"
          ],
          "category": "mitigation",
          "details": "Contact customer support or your local Nucleus Sales team for mitigation advice"
        },
        {
          "product_ids": [
            "1"
          ],
          "category": "no_fix_planned",
          "details": "Currently no remediation is planned"
        },
        {
          "product_ids": [
            "2"
          ],
          "category": "vendor_fix",
          "details": "Update to V2017.02.3 or later version",
          "url": "https://support.sw.siemens.com/en-US/product/1009925838/"
        },
        {
          "product_ids": [
            "4"
          ],
          "category": "vendor_fix",
          "details": "Update to V4.1.0 or later version",
          "url": "https://support.sw.siemens.com/en-US/product/1336134128/"
        },
        {
          "product_ids": [
            "5"
          ],
          "category": "vendor_fix",
          "details": "Contact customer support to receive patch and update information"
        },
        {
          "product_ids": [
            "1",
            "2",
            "4",
            "5"
          ],
          "category": "mitigation",
          "details": "Avoid using DNS client of affected versions"
        }
      ],
      "references": [
        {
          "url": "https://support.sw.siemens.com/en-US/product/1009925838/",
          "summary": "CVE-2020-27736 - Nucleus ReadyStart V3"
        },
        {
          "url": "https://support.sw.siemens.com/en-US/product/1336134128/",
          "summary": "CVE-2020-27736 - Nucleus ReadyStart V4"
        },
        {
          "url": "https://cert-portal.siemens.com/productcert/mitre/CVE-2020-27736.json",
          "summary": "CVE-2020-27736 Mitre 5.0 json"
        }
      ]
    },
    {
      "title": "CVE-2020-27737",
      "notes": [
        {
          "title": "Summary",
          "category": "summary",
          "text": "The DNS response parsing functionality does not properly validate various length and counts of the records. The parsing of malformed responses could result in a read past the end of an allocated structure. An attacker with a privileged position in the network could leverage this vulnerability to cause a denial-of-service condition or leak the memory past the allocated structure."
        }
      ],
      "cve": "CVE-2020-27737",
      "cwe": {
        "id": "CWE-125",
        "name": "Out-of-bounds Read"
      },
      "product_status": {
        "known_affected": [
          "1",
          "2",
          "4",
          "5"
        ]
      },
      "scores": [
        {
          "cvss_v3": {
            "version": "3.1",
            "baseScore": 6.5,
            "baseSeverity": "MEDIUM",
            "vectorString": "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:N/A:H/E:P/RL:O/RC:C"
          },
          "products": [
            "1",
            "2",
            "4",
            "5"
          ]
        }
      ],
      "remediations": [
        {
          "product_ids": [
            "1"
          ],
          "category": "mitigation",
          "details": "Update to the latest version of Nucleus ReadyStart V3 or V4"
        },
        {
          "product_ids": [
            "1"
          ],
          "category": "mitigation",
          "details": "Contact customer support or your local Nucleus Sales team for mitigation advice"
        },
        {
          "product_ids": [
            "1"
          ],
          "category": "no_fix_planned",
          "details": "Currently no remediation is planned"
        },
        {
          "product_ids": [
            "2"
          ],
          "category": "vendor_fix",
          "details": "Update to V2017.02.3 or later version",
          "url": "https://support.sw.siemens.com/en-US/product/1009925838/"
        },
        {
          "product_ids": [
            "4"
          ],
          "category": "vendor_fix",
          "details": "Update to V4.1.0 or later version",
          "url": "https://support.sw.siemens.com/en-US/product/1336134128/"
        },
        {
          "product_ids": [
            "5"
          ],
          "category": "vendor_fix",
          "details": "Contact customer support to receive patch and update information"
        },
        {
          "product_ids": [
            "1",
            "2",
            "4",
            "5"
          ],
          "category": "mitigation",
          "details": "Avoid using DNS client of affected versions"
        }
      ],
      "references": [
        {
          "url": "https://support.sw.siemens.com/en-US/product/1009925838/",
          "summary": "CVE-2020-27737 - Nucleus ReadyStart V3"
        },
        {
          "url": "https://support.sw.siemens.com/en-US/product/1336134128/",
          "summary": "CVE-2020-27737 - Nucleus ReadyStart V4"
        },
        {
          "url": "https://cert-portal.siemens.com/productcert/mitre/CVE-2020-27737.json",
          "summary": "CVE-2020-27737 Mitre 5.0 json"
        }
      ]
    },
    {
      "title": "CVE-2020-27738",
      "notes": [
        {
          "title": "Summary",
          "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 read access past the end of an allocated structure. An attacker with a privileged position in the network could leverage this vulnerability to cause a denial-of-service condition."
        }
      ],
      "cve": "CVE-2020-27738",
      "cwe": {
        "id": "CWE-788",
        "name": "Access of Memory Location After End of Buffer"
      },
      "product_status": {
        "known_affected": [
          "1",
          "2",
          "4",
          "5"
        ]
      },
      "scores": [
        {
          "cvss_v3": {
            "version": "3.1",
            "baseScore": 6.5,
            "baseSeverity": "MEDIUM",
            "vectorString": "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:N/A:H/E:P/RL:O/RC:C"
          },
          "products": [
            "1",
            "2",
            "4",
            "5"
          ]
        }
      ],
      "remediations": [
        {
          "product_ids": [
            "1"
          ],
          "category": "mitigation",
          "details": "Update to the latest version of Nucleus ReadyStart V3 or V4"
        },
        {
          "product_ids": [
            "1"
          ],
          "category": "mitigation",
          "details": "Contact customer support or your local Nucleus Sales team for mitigation advice"
        },
        {
          "product_ids": [
            "1"
          ],
          "category": "no_fix_planned",
          "details": "Currently no remediation is planned"
        },
        {
          "product_ids": [
            "2"
          ],
          "category": "vendor_fix",
          "details": "Update to V2017.02.3 or later version",
          "url": "https://support.sw.siemens.com/en-US/product/1009925838/"
        },
        {
          "product_ids": [
            "4"
          ],
          "category": "vendor_fix",
          "details": "Update to V4.1.0 or later version",
          "url": "https://support.sw.siemens.com/en-US/product/1336134128/"
        },
        {
          "product_ids": [
            "5"
          ],
          "category": "vendor_fix",
          "details": "Contact customer support to receive patch and update information"
        },
        {
          "product_ids": [
            "1",
            "2",
            "4",
            "5"
          ],
          "category": "mitigation",
          "details": "Avoid using DNS client of affected versions"
        }
      ],
      "references": [
        {
          "url": "https://support.sw.siemens.com/en-US/product/1009925838/",
          "summary": "CVE-2020-27738 - Nucleus ReadyStart V3"
        },
        {
          "url": "https://support.sw.siemens.com/en-US/product/1336134128/",
          "summary": "CVE-2020-27738 - Nucleus ReadyStart V4"
        },
        {
          "url": "https://cert-portal.siemens.com/productcert/mitre/CVE-2020-27738.json",
          "summary": "CVE-2020-27738 Mitre 5.0 json"
        }
      ]
    },
    {
      "title": "CVE-2021-25677",
      "notes": [
        {
          "title": "Summary",
          "category": "summary",
          "text": "The DNS client does not properly randomize DNS transaction IDs. That could allow an attacker to poison the DNS cache or spoof DNS resolving."
        }
      ],
      "cve": "CVE-2021-25677",
      "cwe": {
        "id": "CWE-330",
        "name": "Use of Insufficiently Random Values"
      },
      "product_status": {
        "known_affected": [
          "1",
          "2",
          "3",
          "4",
          "5"
        ]
      },
      "scores": [
        {
          "cvss_v3": {
            "version": "3.1",
            "baseScore": 5.3,
            "baseSeverity": "MEDIUM",
            "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N/E:P/RL:O/RC:C"
          },
          "products": [
            "1",
            "2",
            "3",
            "4",
            "5"
          ]
        }
      ],
      "remediations": [
        {
          "product_ids": [
            "1"
          ],
          "category": "mitigation",
          "details": "Update to the latest version of Nucleus ReadyStart V3 or V4"
        },
        {
          "product_ids": [
            "1"
          ],
          "category": "mitigation",
          "details": "Contact customer support or your local Nucleus Sales team for mitigation advice"
        },
        {
          "product_ids": [
            "1"
          ],
          "category": "no_fix_planned",
          "details": "Currently no remediation is planned"
        },
        {
          "product_ids": [
            "2"
          ],
          "category": "vendor_fix",
          "details": "Update to V2017.02.3 or later version",
          "url": "https://support.sw.siemens.com/en-US/product/1009925838/"
        },
        {
          "product_ids": [
            "3"
          ],
          "category": "vendor_fix",
          "details": "Update to V2017.02.4 or later version",
          "url": "https://support.sw.siemens.com/en-US/product/1009925838/"
        },
        {
          "product_ids": [
            "4"
          ],
          "category": "vendor_fix",
          "details": "Update to V4.1.0 or later version",
          "url": "https://support.sw.siemens.com/en-US/product/1336134128/"
        },
        {
          "product_ids": [
            "5"
          ],
          "category": "vendor_fix",
          "details": "Contact customer support to receive patch and update information"
        },
        {
          "product_ids": [
            "1",
            "2",
            "3",
            "4",
            "5"
          ],
          "category": "mitigation",
          "details": "Avoid using DNS client of affected versions"
        }
      ],
      "references": [
        {
          "url": "https://support.sw.siemens.com/en-US/product/1009925838/",
          "summary": "CVE-2021-25677 - Nucleus ReadyStart V3"
        },
        {
          "url": "https://support.sw.siemens.com/en-US/product/1009925838/",
          "summary": "CVE-2021-25677 - Nucleus ReadyStart V3"
        },
        {
          "url": "https://support.sw.siemens.com/en-US/product/1336134128/",
          "summary": "CVE-2021-25677 - Nucleus ReadyStart V4"
        },
        {
          "url": "https://cert-portal.siemens.com/productcert/mitre/CVE-2021-25677.json",
          "summary": "CVE-2021-25677 Mitre 5.0 json"
        }
      ]
    }
  ]
}