{
  "document": {
    "acknowledgments": [
      {
        "organization": "Siemens ProductCERT",
        "summary": "reporting this vulnerability 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/"
      }
    },
    "notes": [
      {
        "category": "summary",
        "text": "The Siveillance Open Interface Services (OIS) application used for integration of different subsystems to several Siemens building management systems contains a command injection vulnerability that could allow a remote unauthenticated attacker to execute code on the affected system with root privileges.\n\nSiemens has released patches and updates for Siveillance OIS to apply to the products that incorporate the OIS service, and recommends to update to the latest versions.",
        "title": "Summary"
      },
      {
        "category": "general",
        "text": "As a general security measure Siemens strongly recommends to protect network access to affected products with appropriate mechanisms. It is advised to follow recommended security practices in order to run the devices in a protected IT environment.",
        "title": "General Recommendations"
      },
      {
        "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": "legal_disclaimer",
        "text": "Siemens Security Advisories are subject to the terms and conditions contained in Siemens\u0027 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\u0027 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.",
        "title": "Terms of Use"
      },
      {
        "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": "other",
        "text": "This CISA CSAF advisory was converted from Siemens ProductCERT\u0027s CSAF advisory.",
        "title": "Advisory Conversion Disclaimer"
      },
      {
        "category": "other",
        "text": "Multiple",
        "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 exploitation risk of these vulnerabilities.",
        "title": "Recommended Practices"
      },
      {
        "category": "general",
        "text": "Minimize network exposure for all control system devices and/or systems, and ensure they are not accessible from the internet.",
        "title": "Recommended Practices"
      },
      {
        "category": "general",
        "text": "Locate control system networks and remote devices behind firewalls and isolate them from business networks.",
        "title": "Recommended Practices"
      },
      {
        "category": "general",
        "text": "When remote access is required, use more secure methods, such as Virtual Private Networks (VPNs), recognizing VPNs may have vulnerabilities and should be updated to the most recent version available. Also recognize VPN is only as secure as its connected devices.",
        "title": "Recommended Practices"
      },
      {
        "category": "general",
        "text": "CISA reminds organizations to perform proper impact analysis and risk assessment prior to deploying defensive measures.",
        "title": "Recommended Practices"
      },
      {
        "category": "general",
        "text": "CISA also provides a section for control systems security recommended practices on the ICS webpage on cisa.gov. Several CISA products detailing cyber defense best practices are available for reading and download, including Improving Industrial Control Systems Cybersecurity with Defense-in-Depth Strategies.",
        "title": "Recommended Practices"
      },
      {
        "category": "general",
        "text": "CISA encourages organizations to implement recommended cybersecurity strategies for proactive defense of ICS assets. Additional mitigation guidance and recommended practices are publicly available on the ICS webpage at cisa.gov in the technical information paper, ICS-TIP-12-146-01B--Targeted Cyber Intrusion Detection and Mitigation Strategies.",
        "title": "Recommended Practices"
      },
      {
        "category": "general",
        "text": "Organizations observing suspected malicious activity should follow established internal procedures and report findings to CISA for tracking and correlation against other incidents.",
        "title": "Recommended Practices"
      }
    ],
    "publisher": {
      "category": "other",
      "contact_details": "central@cisa.dhs.gov",
      "name": "CISA",
      "namespace": "https://www.cisa.gov/"
    },
    "references": [
      {
        "category": "self",
        "summary": "SSA-535380: Command Injection Vulnerability in Siveillance OIS Affecting Several Building Management Systems - CSAF Version",
        "url": "https://cert-portal.siemens.com/productcert/csaf/ssa-535380.json"
      },
      {
        "category": "self",
        "summary": "SSA-535380: Command Injection Vulnerability in Siveillance OIS Affecting Several Building Management Systems - TXT Version",
        "url": "https://cert-portal.siemens.com/productcert/txt/ssa-535380.txt"
      },
      {
        "category": "self",
        "summary": "SSA-535380: Command Injection Vulnerability in Siveillance OIS Affecting Several Building Management Systems - PDF Version",
        "url": "https://cert-portal.siemens.com/productcert/pdf/ssa-535380.pdf"
      },
      {
        "category": "self",
        "summary": "ICS Advisory ICSA-21-257-18 JSON",
        "url": "https://raw.githubusercontent.com/cisagov/CSAF/develop/csaf_files/OT/white/2021/icsa-21-257-18.json"
      },
      {
        "category": "self",
        "summary": "ICS Advisory ICSA-21-257-18 - Web Version",
        "url": "https://www.cisa.gov/news-events/ics-advisories/icsa-21-257-18"
      },
      {
        "category": "external",
        "summary": "Recommended Practices",
        "url": "https://www.cisa.gov/uscert/ics/alerts/ICS-ALERT-10-301-01"
      },
      {
        "category": "external",
        "summary": "Recommended Practices",
        "url": "https://www.cisa.gov/resources-tools/resources/ics-recommended-practices"
      },
      {
        "category": "external",
        "summary": "Recommended Practices",
        "url": "https://www.cisa.gov/topics/industrial-control-systems"
      },
      {
        "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://www.cisa.gov/sites/default/files/publications/Cybersecurity_Best_Practices_for_Industrial_Control_Systems.pdf"
      },
      {
        "category": "external",
        "summary": "Recommended Practices",
        "url": "https://www.cisa.gov/uscert/ics/tips/ICS-TIP-12-146-01B"
      }
    ],
    "title": "Siemens Siveillance OIS",
    "tracking": {
      "current_release_date": "2025-05-06T06:00:00.000000Z",
      "generator": {
        "engine": {
          "name": "CISA CSAF Generator",
          "version": "1.0.0"
        }
      },
      "id": "ICSA-21-257-18",
      "initial_release_date": "2021-09-14T00:00:00.000000Z",
      "revision_history": [
        {
          "date": "2021-09-14T00:00:00.000000Z",
          "legacy_version": "1.0",
          "number": "1",
          "summary": "Publication Date"
        },
        {
          "date": "2025-05-06T06:00:00.000000Z",
          "legacy_version": "Revision",
          "number": "2",
          "summary": "Revision - Fixing typos"
        }
      ],
      "status": "final",
      "version": "2"
    }
  },
  "product_tree": {
    "branches": [
      {
        "branches": [
          {
            "branches": [
              {
                "category": "product_version_range",
                "name": "All_versions_with_OIS_Extension_Module",
                "product": {
                  "name": "Desigo CC",
                  "product_id": "CSAFPID-0001"
                }
              }
            ],
            "category": "product_name",
            "name": "Desigo CC"
          },
          {
            "branches": [
              {
                "category": "product_version_range",
                "name": "\u003c=with_OIS_running_on_Debian_9",
                "product": {
                  "name": "GMA-Manager",
                  "product_id": "CSAFPID-0002"
                }
              }
            ],
            "category": "product_name",
            "name": "GMA-Manager"
          },
          {
            "branches": [
              {
                "category": "product_version_range",
                "name": "\u003c=with_OIS_running_on_Debian_9",
                "product": {
                  "name": "Operation Scheduler",
                  "product_id": "CSAFPID-0003"
                }
              }
            ],
            "category": "product_name",
            "name": "Operation Scheduler"
          },
          {
            "branches": [
              {
                "category": "product_version_range",
                "name": "\u003c=with_OIS_running_on_Debian_9",
                "product": {
                  "name": "Siveillance Control",
                  "product_id": "CSAFPID-0004"
                }
              }
            ],
            "category": "product_name",
            "name": "Siveillance Control"
          },
          {
            "branches": [
              {
                "category": "product_version_range",
                "name": "vers:all/*",
                "product": {
                  "name": "Siveillance Control Pro",
                  "product_id": "CSAFPID-0005"
                }
              }
            ],
            "category": "product_name",
            "name": "Siveillance Control Pro"
          }
        ],
        "category": "vendor",
        "name": "Siemens"
      }
    ]
  },
  "vulnerabilities": [
    {
      "cve": "CVE-2021-31891",
      "cwe": {
        "id": "CWE-78",
        "name": "Improper Neutralization of Special Elements used in an OS Command (\u0027OS Command Injection\u0027)"
      },
      "notes": [
        {
          "category": "summary",
          "text": "The affected application incorrectly neutralizes special elements in a specific HTTP GET request which could lead to command injection.\n\nAn unauthenticated remote attacker could exploit this vulnerability to execute arbitrary code on the system with root privileges.",
          "title": "Summary"
        }
      ],
      "product_status": {
        "known_affected": [
          "CSAFPID-0001",
          "CSAFPID-0002",
          "CSAFPID-0003",
          "CSAFPID-0004",
          "CSAFPID-0005"
        ]
      },
      "references": [
        {
          "summary": "CVE-2021-31891 - Desigo CC",
          "url": "https://support.industry.siemens.com/cs/ww/en/view/109799908/"
        },
        {
          "summary": "CVE-2021-31891 - GMA-Manager",
          "url": "https://support.industry.siemens.com/cs/ww/en/view/109799908/"
        },
        {
          "summary": "CVE-2021-31891 - Operation Scheduler",
          "url": "https://support.industry.siemens.com/cs/ww/en/view/109799908/"
        },
        {
          "summary": "CVE-2021-31891 - Siveillance Control",
          "url": "https://support.industry.siemens.com/cs/ww/en/view/109799908/"
        },
        {
          "summary": "CVE-2021-31891 - Siveillance Control Pro",
          "url": "https://support.industry.siemens.com/cs/ww/en/view/109799908/"
        },
        {
          "summary": "CVE-2021-31891 Mitre 5.0 json",
          "url": "https://cert-portal.siemens.com/productcert/mitre/CVE-2021-31891.json"
        }
      ],
      "remediations": [
        {
          "category": "vendor_fix",
          "details": "Update the OIS to V2.5.3 or apply the patch",
          "product_ids": [
            "CSAFPID-0001",
            "CSAFPID-0002",
            "CSAFPID-0003"
          ],
          "url": "https://support.industry.siemens.com/cs/ww/en/view/109799908/"
        },
        {
          "category": "vendor_fix",
          "details": "Update the OIS to V2.5.3 or V2.6.1, or apply the patch",
          "product_ids": [
            "CSAFPID-0004"
          ],
          "url": "https://support.industry.siemens.com/cs/ww/en/view/109799908/"
        },
        {
          "category": "vendor_fix",
          "details": "Update the OIS to V2.5.3 or V2.6.0, or apply the patch",
          "product_ids": [
            "CSAFPID-0005"
          ],
          "url": "https://support.industry.siemens.com/cs/ww/en/view/109799908/"
        },
        {
          "category": "mitigation",
          "details": "Ensure that the systems where Siveillance OIS is installed are only accessible by trusted personnel",
          "product_ids": [
            "CSAFPID-0001",
            "CSAFPID-0002",
            "CSAFPID-0003",
            "CSAFPID-0004",
            "CSAFPID-0005"
          ]
        },
        {
          "category": "mitigation",
          "details": "Restrict access to the affected systems, especially to port 443/tcp, to trusted IP addresses only",
          "product_ids": [
            "CSAFPID-0001",
            "CSAFPID-0002",
            "CSAFPID-0003",
            "CSAFPID-0004",
            "CSAFPID-0005"
          ]
        }
      ],
      "scores": [
        {
          "cvss_v3": {
            "baseScore": 10.0,
            "baseSeverity": "CRITICAL",
            "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H/E:P/RL:O/RC:C",
            "version": "3.1"
          },
          "products": [
            "CSAFPID-0001",
            "CSAFPID-0002",
            "CSAFPID-0003",
            "CSAFPID-0004",
            "CSAFPID-0005"
          ]
        }
      ],
      "title": "CVE-2021-31891"
    }
  ]
}