{
  "document": {
    "category": "csaf_security_advisory",
    "csaf_version": "2.0",
    "distribution": {
      "text": "Public",
      "tlp": {
        "label": "WHITE"
      }
    },
    "lang": "en-US",
    "notes": [
      {
        "category": "general",
        "text": "We strongly recommend the following industry cybersecurity best practices.\n\n* Locate control and safety system networks and remote devices behind firewalls and isolate them from the business network.\n* Install physical controls so no unauthorized personnel can access your industrial control and safety systems, components, peripheral equipment, and networks.\n* Place all controllers in locked cabinets and never leave them in the \u201cProgram\u201d mode.\n* Never connect programming software to any network other than the network intended for that device.\n* Scan all methods of mobile data exchange with the isolated network such as CDs, USB drives, etc. before use in the terminals or any node connected to these networks.\n* Never allow mobile devices that have connected to any other network besides the intended network to connect to the safety or control networks without proper sanitation.\n* Minimize network exposure for all control system devices and systems and ensure that they are not accessible from the Internet.\n* When remote access is required, use secure methods, such as Virtual Private Networks (VPNs). Recognize that VPNs may have vulnerabilities and should be updated to the most current version available. Also, understand that VPNs are only as secure as the connected devices.\n\nFor more information refer to the Schneider Electric [Recommended Cybersecurity Best Practices](https://www.se.com/us/en/download/document/7EN52-0390/) document.",
        "title": "General Security Recommendations"
      },
      {
        "category": "general",
        "text": "This document provides an overview of the identified vulnerability or vulnerabilities and actions required to mitigate. For more details and assistance on how to protect your installation, contact your local Schneider Electric representative or Schneider Electric Industrial Cybersecurity Services: https://www.se.com/ww/en/work/solutions/cybersecurity/. These organizations will be fully aware of this situation and can support you through the process.\n\nFor further information related to cybersecurity in Schneider Electric\u0027s products, visit the company\u0027s cybersecurity support portal page: https://www.se.com/ww/en/work/support/cybersecurity/overview.jsp",
        "title": "For More Information"
      },
      {
        "category": "legal_disclaimer",
        "text": "THIS NOTIFICATION DOCUMENT, THE INFORMATION CONTAINED HEREIN, AND ANY MATERIALS LINKED FROM IT (COLLECTIVELY, THIS \u201cNOTIFICATION\u201d) ARE INTENDED TO HELP PROVIDE AN OVERVIEW OF THE IDENTIFIED SITUATION AND SUGGESTED MITIGATION ACTIONS, REMEDIATION, FIX, AND/OR GENERAL SECURITY RECOMMENDATIONS AND IS PROVIDED ON AN \u201cAS-IS\u201d BASIS WITHOUT WARRANTY OR GUARANTEE OF ANY KIND.  SCHNEIDER ELECTRIC DISCLAIMS ALL WARRANTIES RELATING TO THIS NOTIFICATION, EITHER EXPRESS OR IMPLIED, INCLUDING WARRANTIES OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE. SCHNEIDER ELECTRIC MAKES NO WARRANTY THAT THE NOTIFICATION WILL RESOLVE THE IDENTIFIED SITUATION. IN NO EVENT SHALL SCHNEIDER ELECTRIC BE LIABLE FOR ANY DAMAGES OR LOSSES WHATSOEVER IN CONNECTION WITH THIS NOTIFICATION, INCLUDING DIRECT, INDIRECT, INCIDENTAL, CONSEQUENTIAL, LOSS OF BUSINESS PROFITS OR SPECIAL DAMAGES, EVEN IF SCHNEIDER ELECTRIC HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH DAMAGES. YOUR USE OF THIS NOTIFICATION IS AT YOUR OWN RISK, AND YOU ARE SOLELY LIABLE FOR ANY DAMAGES TO YOUR SYSTEMS OR ASSETS OR OTHER LOSSES THAT MAY RESULT FROM YOUR USE OF THIS NOTIFICATION. SCHNEIDER ELECTRIC RESERVES THE RIGHT TO UPDATE OR CHANGE THIS NOTIFICATION AT ANY TIME AND IN ITS SOLE DISCRETION",
        "title": "LEGAL DISCLAIMER"
      },
      {
        "category": "general",
        "text": "Schneider\u0027s purpose is to create Impact by empowering all to make the most of our energy and resources, bridging progress and\r\nsustainability for all. We call this Life Is On.\n\nOur mission is to be the trusted partner in Sustainability and Efficiency.\n\nWe are a global industrial technology leader bringing world-leading expertise in electrification, automation and digitization to smart\r\nindustries, resilient infrastructure, future-proof data centers, intelligent buildings, and intuitive homes. Anchored by our deep\r\ndomain expertise, we provide integrated end-to-end lifecycle AI enabled Industrial IoT solutions with connected products, automation,\r\nsoftware and services, delivering digital twins to enable profitable growth for our customers.\n\nWe are a people company with an ecosystem of 150,000 colleagues and more than a million partners operating in over 100 countries\r\nto ensure proximity to our customers and stakeholders. We embrace diversity and inclusion in everything we do, guided by our\r\nmeaningful purpose of a sustainable future for all. \n\n www.se.com",
        "title": "About Schneider Electric"
      },
      {
        "category": "summary",
        "text": "Schneider Electric is aware of a vulnerability in its Modicon M580 and Modicon M580 Safety controllers. \r\nThe Modicon M580 is an Ethernet-based Programmable Automation Controller (ePAC) designed for industrial digital transformation.\r\nFailure to apply the remediations provided below may risk establishing an unauthenticated connection to Modicon M580 or M580 Safety controllers which could result in loss of confidentiality, integrity and availability of the PLC.",
        "title": "Overview"
      },
      {
        "category": "other",
        "text": "The severity of vulnerabilities was calculated using the CVSS Base metrics for 4.0 ([CVSS v4.0](https://www.first.org/cvss/calculator/4.0)). CVSS v3.1 \nwill be still evaluated until the adoption of CVSS v4.0 by the industry. The severity was calculated without \nincorporating the Temporal and Environmental metrics. Schneider Electric recommends that customers score the CVSS Environmental metrics, which are specific to end-user organizations, and consider factors such as \nthe presence of mitigations in that environment. Environmental metrics may refine the relative severity posed by the vulnerabilities described in this document within a customer\u0027s environment."
      },
      {
        "category": "other",
        "text": "Customers should use appropriate patching methodologies when applying these patches to their systems. We strongly recommend the use of back-ups and evaluating the impact of these patches in a Test and Development environment or on an offline infrastructure. Contact Schneider Electric\u0027s [Customer Care Center](https://www.se.com/us/en/work/support/contacts.jsp) if you need assistance removing a patch. "
      }
    ],
    "publisher": {
      "category": "vendor",
      "contact_details": "cpcert@se.com",
      "name": "Schneider Electric CPCERT",
      "namespace": "https://www.se.com/ww/en/work/support/cybersecurity/security-notifications.jsp"
    },
    "references": [
      {
        "category": "self",
        "summary": "Incorrect Implementation of Authentication Algorithm vulnerability on Modicon M580 and Modicon M580 Safety - SEVD-2026-251-04 PDF Version",
        "url": "https://download.schneider-electric.com/files?p_Doc_Ref=SEVD-2026-251-04\u0026p_enDocType=Security+and+Safety+Notice\u0026p_File_Name=SEVD-2026-251-04.pdf"
      },
      {
        "category": "self",
        "summary": "Incorrect Implementation of Authentication Algorithm vulnerability on Modicon M580 and Modicon M580 Safety - SEVD-2026-251-04 CSAF Version",
        "url": "https://download.schneider-electric.com/files?p_Doc_Ref=SEVD-2026-251-04\u0026p_enDocType=Security+and+Safety+Notice\u0026p_File_Name=sevd-2026-251-04.json"
      },
      {
        "category": "external",
        "summary": "Recommended Cybersecurity Best Practices",
        "url": "https://www.se.com/ww/en/download/document/7EN52-0390/"
      }
    ],
    "title": "Incorrect Implementation of Authentication Algorithm vulnerability on Modicon M580 and Modicon M580 Safety",
    "tracking": {
      "current_release_date": "2026-09-08T07:00:00.000Z",
      "generator": {
        "date": "2026-09-07T08:32:18.606Z",
        "engine": {
          "name": "Schneider Electric CSAF Generator",
          "version": "1.2"
        }
      },
      "id": "SEVD-2026-251-04",
      "initial_release_date": "2026-09-08T07:00:00.000Z",
      "revision_history": [
        {
          "date": "2026-09-08T07:00:00.000Z",
          "number": "1.0.0",
          "summary": "Original Release"
        }
      ],
      "status": "final",
      "version": "1.0.0"
    }
  },
  "product_tree": {
    "branches": [
      {
        "branches": [
          {
            "category": "product_name",
            "name": "Modicon M580",
            "product": {
              "name": "Modicon M580 All versions with an application level below 4.00",
              "product_id": "1"
            }
          },
          {
            "category": "product_name",
            "name": "Modicon M580 Safety",
            "product": {
              "name": "Modicon M580 Safety All versions with an application level below 4.20",
              "product_id": "2"
            }
          },
          {
            "branches": [
              {
                "category": "product_version_range",
                "name": "vers:intdot/\u003e=4.10",
                "product": {
                  "name": "Modicon M580 firmware version 4.10 or above running an application project with application level 4.00 or above",
                  "product_id": "3"
                }
              }
            ],
            "category": "product_name",
            "name": "Modicon M580 firmware"
          },
          {
            "branches": [
              {
                "category": "product_version_range",
                "name": "vers:intdot/\u003e=4.21",
                "product": {
                  "name": "Modicon M580 Safety firmware version 4.21 or above running an application project with application level 4.20 or above",
                  "product_id": "4"
                }
              }
            ],
            "category": "product_name",
            "name": "Modicon M580 Safety firmware"
          }
        ],
        "category": "vendor",
        "name": "Schneider Electric"
      }
    ]
  },
  "vulnerabilities": [
    {
      "acknowledgments": [
        {
          "names": [
            "Schneider Electric Partner"
          ]
        }
      ],
      "cve": "CVE-2026-3869",
      "cwe": {
        "id": "CWE-303",
        "name": "Incorrect Implementation of Authentication Algorithm"
      },
      "notes": [
        {
          "category": "description",
          "text": "CWE-303: Incorrect Implementation of Authentication Algorithm vulnerability exists that could cause loss of confidentiality, integrity and availability of the PLC provided an application project with a lower application level is running on the PLC.",
          "title": "CVE Description"
        },
        {
          "category": "details",
          "text": "CVSS v4.0 Base Score 9.2 | Critical | [CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N](https://www.first.org/cvss/calculator/4.0#CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N)",
          "title": "CVSS v4.0 Base Score"
        }
      ],
      "product_status": {
        "fixed": [
          "3",
          "4"
        ],
        "known_affected": [
          "1",
          "2"
        ]
      },
      "remediations": [
        {
          "category": "vendor_fix",
          "details": "Ensure to use firmware version 4.10 or above\r\n\r\nAND \r\n\r\nUpdate your application project to application level 4.00 or above. Application level 4.00 is available in EcoStruxure Control Expert V15.2 or later versions.",
          "product_ids": [
            "1"
          ],
          "restart_required": {
            "category": "system"
          }
        },
        {
          "category": "vendor_fix",
          "details": "Ensure to use firmware version 4.21 or above\r\n\r\nAND \r\n\r\nUpdate your application project to application level 4.20 or above. Application level 4.20 is available in EcoStruxure Control Expert V16.0 with HF001 installed or later versions.",
          "product_ids": [
            "2"
          ],
          "restart_required": {
            "category": "system"
          }
        }
      ],
      "scores": [
        {
          "cvss_v3": {
            "attackComplexity": "LOW",
            "attackVector": "NETWORK",
            "availabilityImpact": "HIGH",
            "baseScore": 9.8,
            "baseSeverity": "CRITICAL",
            "confidentialityImpact": "HIGH",
            "integrityImpact": "HIGH",
            "privilegesRequired": "NONE",
            "scope": "UNCHANGED",
            "userInteraction": "NONE",
            "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H",
            "version": "3.1"
          },
          "products": [
            "1",
            "2"
          ]
        }
      ],
      "title": "CVE-2026-3869"
    }
  ]
}