ICSA-26-062-01

Vulnerability from csaf_cisa - Published: 2026-03-03 00:00 - Updated: 2026-03-03 07:00
Summary
Mitsubishi Electric MELSEC iQ-F Series EtherNet/IP module and Ethernet module

Notes

Risk evaluation
Successful exploitation of these vulnerabilities could allow a remote attacker to cause a denial-of-service condition by continuously sending UDP packets to the affected products.
Legal Notice and Terms of Use
This product is provided subject to this notification (https://www.cisa.gov/notification) and this privacy & use policy (https://www.cisa.gov/privacy-policy).
Advisory Conversion Disclaimer
This ICSA is a republication of Mitsubishi Electric security advisory "2025-021 Multiple denial-of-service vulnerabilities in Ethernet function of MELSEC iQ-F Series EtherNet/IP module and Ethernet module" from a direct conversion of the vendor's Common Security Advisory Framework (CSAF) advisory. This is republished to CISA's website as a means of increasing visibility and is provided "as-is" for informational purposes only. CISA is not responsible for the editorial or technical accuracy of republished advisories and provides no warranties of any kind regarding any information contained within this advisory. Further, CISA does not endorse any commercial product or service. Please contact CISA directly for any questions regarding this advisory.
Critical infrastructure sectors
Critical Manufacturing
Countries/areas deployed
Worldwide
Company headquarters location
Japan
Recommended Practices
CISA recommends users take defensive measures to minimize the risk of exploitation of these vulnerabilities. CISA reminds organizations to perform proper impact analysis and risk assessment prior to deploying defensive measures.
Recommended Practices
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.
Recommended Practices
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.
Recommended Practices
Organizations observing suspected malicious activity should follow established internal procedures and report findings to CISA for tracking and correlation against other incidents.
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        "title": "Risk evaluation"
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      {
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      },
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        "title": "Advisory Conversion Disclaimer"
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      {
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      {
        "category": "general",
        "text": "CISA recommends users take defensive measures to minimize the risk of exploitation of these vulnerabilities. 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",
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        "title": "Recommended Practices"
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        "url": "https://www.cisa.gov/news-events/news/targeted-cyber-intrusion-detection-and-mitigation-strategies-update-b"
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    ],
    "title": "Mitsubishi Electric MELSEC iQ-F Series EtherNet/IP module and Ethernet module",
    "tracking": {
      "current_release_date": "2026-03-03T07:00:00.000000Z",
      "generator": {
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  "product_tree": {
    "branches": [
      {
        "branches": [
          {
            "branches": [
              {
                "category": "product_version_range",
                "name": "\u003c=1.106",
                "product": {
                  "name": "Mitsubishi Electric MELSEC iQ-F Series FX5-ENET/IP Ethernet Module FX5-ENET/IP: \u003c=1.106",
                  "product_id": "CSAFPID-0001"
                }
              },
              {
                "category": "product_version_range",
                "name": "vers:all/*",
                "product": {
                  "name": "Mitsubishi Electric MELSEC iQ-F Series FX5-ENET/IP Ethernet Module FX5-ENET/IP: vers:all/*",
                  "product_id": "CSAFPID-0002"
                }
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            ],
            "category": "product_name",
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                "product": {
                  "name": "Mitsubishi Electric MELSEC iQ-F Series FX5-EIP EtherNet/IP Module FX5-EIP: vers:all/*",
                  "product_id": "CSAFPID-0003"
                }
              }
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            "category": "product_name",
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          }
        ],
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        "name": "Mitsubishi Electric"
      }
    ]
  },
  "vulnerabilities": [
    {
      "cve": "CVE-2026-1874",
      "cwe": {
        "id": "CWE-670",
        "name": "Always-Incorrect Control Flow Implementation"
      },
      "notes": [
        {
          "category": "summary",
          "text": "An always-incorrect control flow implementation vulnerability may allow a remote attacker to cause a denial-of-service condition by continuously sending UDP packets to the affected products. ",
          "title": "Vulnerability Summary"
        },
        {
          "category": "details",
          "text": "SSVCv2/E:N/A:Y/T:P/2026-03-03T00:00:00Z/",
          "title": "SSVC"
        }
      ],
      "product_status": {
        "known_affected": [
          "CSAFPID-0001",
          "CSAFPID-0003"
        ]
      },
      "references": [
        {
          "category": "external",
          "summary": "www.first.org",
          "url": "https://www.first.org/cvss/calculator/4.0#CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N"
        },
        {
          "category": "external",
          "summary": "www.cve.org",
          "url": "https://www.cve.org/CVERecord?id=CVE-2026-1874"
        },
        {
          "category": "external",
          "summary": "cwe.mitre.org",
          "url": "https://cwe.mitre.org/data/definitions/670.html"
        },
        {
          "category": "external",
          "summary": "www.first.org",
          "url": "https://www.first.org/cvss/calculator/3.1#CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H"
        }
      ],
      "remediations": [
        {
          "category": "vendor_fix",
          "details": "Users of FX5-ENET/IP versions 1.106 and prior should download the update file for version 1.107 or later and apply it. The update file is available at: https://www.mitsubishielectric.com/fa/download/index.html.",
          "product_ids": [
            "CSAFPID-0001"
          ],
          "url": "https://www.mitsubishielectric.com/fa/download/index.html"
        },
        {
          "category": "mitigation",
          "details": "The fixed version for the FX5-EIP is scheduled to be released in the near future. In the meantime, users should apply mitigations or workarounds.",
          "product_ids": [
            "CSAFPID-0003"
          ]
        },
        {
          "category": "mitigation",
          "details": "For users of products that do not have a fixed version or who cannot immediately update the product, Mitsubishi Electric recommends using a firewall, virtual private network (VPN), etc. and preventing unauthorized access when internet access is required, to minimize the risk of exploiting this vulnerability.",
          "product_ids": [
            "CSAFPID-0001",
            "CSAFPID-0003"
          ]
        },
        {
          "category": "mitigation",
          "details": "For users of products that do not have a fixed version or who cannot immediately update the product, Mitsubishi Electric recommends using the affected product within a LAN and blocking access from untrusted networks and hosts through firewalls, to minimize the risk of exploiting this vulnerability.",
          "product_ids": [
            "CSAFPID-0001",
            "CSAFPID-0003"
          ]
        },
        {
          "category": "mitigation",
          "details": "For users of products that do not have a fixed version or who cannot immediately update the product, Mitsubishi Electric recommends using the IP filter function of the affected product and blocking access from untrusted hosts, to minimize the risk of exploiting this vulnerability. For details on the IP filter function, refer to \u201c13.1 IP Filter Function\u201d in the MELSEC iQ-F FX5 User\u2019s Manual (Communication).",
          "product_ids": [
            "CSAFPID-0001",
            "CSAFPID-0003"
          ]
        },
        {
          "category": "mitigation",
          "details": "For users of products that do not have a fixed version or who cannot immediately update the product, Mitsubishi Electric recommends restricting physical access to the affected product, as well as to PCs and network devices to which it is connected, to minimize the risk of exploiting this vulnerability.",
          "product_ids": [
            "CSAFPID-0001",
            "CSAFPID-0003"
          ]
        },
        {
          "category": "mitigation",
          "details": "For users of products that do not have a fixed version or who cannot immediately update the product, Mitsubishi Electric recommends installing anti-virus software on PCs that can access the affected product, to minimize the risk of exploiting this vulnerability.",
          "product_ids": [
            "CSAFPID-0001",
            "CSAFPID-0003"
          ]
        },
        {
          "category": "mitigation",
          "details": "For more information, see Mitsubishi Electric 2025-021. https://www.mitsubishielectric.com/psirt/vulnerability/pdf/2025-021_en.pdf ",
          "product_ids": [
            "CSAFPID-0001",
            "CSAFPID-0003"
          ],
          "url": "https://www.mitsubishielectric.com/psirt/vulnerability/pdf/2025-021_en.pdf"
        }
      ],
      "scores": [
        {
          "cvss_v3": {
            "attackComplexity": "LOW",
            "attackVector": "NETWORK",
            "availabilityImpact": "HIGH",
            "baseScore": 7.5,
            "baseSeverity": "HIGH",
            "confidentialityImpact": "NONE",
            "integrityImpact": "NONE",
            "privilegesRequired": "NONE",
            "scope": "UNCHANGED",
            "userInteraction": "NONE",
            "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H",
            "version": "3.1"
          },
          "products": [
            "CSAFPID-0001",
            "CSAFPID-0003"
          ]
        }
      ]
    },
    {
      "cve": "CVE-2026-1875",
      "cwe": {
        "id": "CWE-404",
        "name": "Improper Resource Shutdown or Release"
      },
      "notes": [
        {
          "category": "summary",
          "text": "An improper resource shutdown or release vulnerability in the affected products may allow a remote attacker to cause a denial-of-service condition by continuously sending UDP packets. ",
          "title": "Vulnerability Summary"
        },
        {
          "category": "details",
          "text": "SSVCv2/E:N/A:Y/T:P/2026-03-03T00:00:00Z/",
          "title": "SSVC"
        }
      ],
      "product_status": {
        "known_affected": [
          "CSAFPID-0003"
        ]
      },
      "references": [
        {
          "category": "external",
          "summary": "www.first.org",
          "url": "https://www.first.org/cvss/calculator/4.0#CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N"
        },
        {
          "category": "external",
          "summary": "www.cve.org",
          "url": "https://www.cve.org/CVERecord?id=CVE-2026-1875"
        },
        {
          "category": "external",
          "summary": "cwe.mitre.org",
          "url": "https://cwe.mitre.org/data/definitions/404.html"
        },
        {
          "category": "external",
          "summary": "www.first.org",
          "url": "https://www.first.org/cvss/calculator/3.1#CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H"
        }
      ],
      "remediations": [
        {
          "category": "mitigation",
          "details": "The fixed version for the FX5-EIP is scheduled to be released in the near future. In the meantime, users should apply mitigations or workarounds.",
          "product_ids": [
            "CSAFPID-0003"
          ]
        },
        {
          "category": "mitigation",
          "details": "For users of products that do not have a fixed version or who cannot immediately update the product, Mitsubishi Electric recommends using a firewall, virtual private network (VPN), etc. and preventing unauthorized access when internet access is required, to minimize the risk of exploiting this vulnerability.",
          "product_ids": [
            "CSAFPID-0003"
          ]
        },
        {
          "category": "mitigation",
          "details": "For users of products that do not have a fixed version or who cannot immediately update the product, Mitsubishi Electric recommends using the affected product within a LAN and blocking access from untrusted networks and hosts through firewalls, to minimize the risk of exploiting this vulnerability.",
          "product_ids": [
            "CSAFPID-0003"
          ]
        },
        {
          "category": "mitigation",
          "details": "For users of products that do not have a fixed version or who cannot immediately update the product, Mitsubishi Electric recommends using the IP filter function of the affected product and blocking access from untrusted hosts, to minimize the risk of exploiting this vulnerability. For details on the IP filter function, refer to \u201c13.1 IP Filter Function\u201d in the MELSEC iQ-F FX5 User\u2019s Manual (Communication).",
          "product_ids": [
            "CSAFPID-0003"
          ]
        },
        {
          "category": "mitigation",
          "details": "For users of products that do not have a fixed version or who cannot immediately update the product, Mitsubishi Electric recommends restricting physical access to the affected product, as well as to PCs and network devices to which it is connected, to minimize the risk of exploiting this vulnerability.",
          "product_ids": [
            "CSAFPID-0003"
          ]
        },
        {
          "category": "mitigation",
          "details": "For users of products that do not have a fixed version or who cannot immediately update the product, Mitsubishi Electric recommends installing anti-virus software on PCs that can access the affected product, to minimize the risk of exploiting this vulnerability.",
          "product_ids": [
            "CSAFPID-0003"
          ]
        },
        {
          "category": "mitigation",
          "details": "For more information, see Mitsubishi Electric 2025-021. https://www.mitsubishielectric.com/psirt/vulnerability/pdf/2025-021_en.pdf ",
          "product_ids": [
            "CSAFPID-0003"
          ],
          "url": "https://www.mitsubishielectric.com/psirt/vulnerability/pdf/2025-021_en.pdf"
        }
      ],
      "scores": [
        {
          "cvss_v3": {
            "attackComplexity": "LOW",
            "attackVector": "NETWORK",
            "availabilityImpact": "HIGH",
            "baseScore": 7.5,
            "baseSeverity": "HIGH",
            "confidentialityImpact": "NONE",
            "integrityImpact": "NONE",
            "privilegesRequired": "NONE",
            "scope": "UNCHANGED",
            "userInteraction": "NONE",
            "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H",
            "version": "3.1"
          },
          "products": [
            "CSAFPID-0003"
          ]
        }
      ]
    },
    {
      "cve": "CVE-2026-1876",
      "cwe": {
        "id": "CWE-404",
        "name": "Improper Resource Shutdown or Release"
      },
      "notes": [
        {
          "category": "summary",
          "text": "An improper resource shutdown or release vulnerability may allow a remote attacker to cause a denial-of-service condition in the affected products by continuously sending UDP packets.",
          "title": "Vulnerability Summary"
        },
        {
          "category": "details",
          "text": "SSVCv2/E:N/A:Y/T:P/2026-03-03T00:00:00Z/",
          "title": "SSVC"
        }
      ],
      "product_status": {
        "known_affected": [
          "CSAFPID-0002"
        ]
      },
      "references": [
        {
          "category": "external",
          "summary": "www.first.org",
          "url": "https://www.first.org/cvss/calculator/4.0#CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N"
        },
        {
          "category": "external",
          "summary": "www.cve.org",
          "url": "https://www.cve.org/CVERecord?id=CVE-2026-1876"
        },
        {
          "category": "external",
          "summary": "cwe.mitre.org",
          "url": "https://cwe.mitre.org/data/definitions/404.html"
        },
        {
          "category": "external",
          "summary": "www.first.org",
          "url": "https://www.first.org/cvss/calculator/3.1#CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H"
        }
      ],
      "remediations": [
        {
          "category": "no_fix_planned",
          "details": "Users should apply mitigations or workarounds since there are no plans to release a fixed version.",
          "product_ids": [
            "CSAFPID-0002"
          ]
        },
        {
          "category": "mitigation",
          "details": "For users of products that do not have a fixed version, Mitsubishi Electric recommends using a firewall, virtual private network (VPN), etc. and preventing unauthorized access when internet access is required, to minimize the risk of exploiting this vulnerability.",
          "product_ids": [
            "CSAFPID-0002"
          ]
        },
        {
          "category": "mitigation",
          "details": "For users of products that do not have a fixed version, Mitsubishi Electric recommends using the affected product within a LAN and blocking access from untrusted networks and hosts through firewalls, to minimize the risk of exploiting this vulnerability.",
          "product_ids": [
            "CSAFPID-0002"
          ]
        },
        {
          "category": "mitigation",
          "details": "For users of products that do not have a fixed version, Mitsubishi Electric recommends using the IP filter function of the affected product and blocking access from untrusted hosts, to minimize the risk of exploiting this vulnerability. For details on the IP filter function, refer to \u201c13.1 IP Filter Function\u201d in the MELSEC iQ-F FX5 User\u2019s Manual (Communication).",
          "product_ids": [
            "CSAFPID-0002"
          ]
        },
        {
          "category": "mitigation",
          "details": "For users of products that do not have a fixed version, Mitsubishi Electric recommends restricting physical access to the affected product, as well as to PCs and network devices to which it is connected, to minimize the risk of exploiting this vulnerability.",
          "product_ids": [
            "CSAFPID-0002"
          ]
        },
        {
          "category": "mitigation",
          "details": "For users of products that do not have a fixed version, Mitsubishi Electric recommends installing anti-virus software on PCs that can access the affected product, to minimize the risk of exploiting this vulnerability.",
          "product_ids": [
            "CSAFPID-0002"
          ]
        },
        {
          "category": "mitigation",
          "details": "For more information, see Mitsubishi Electric 2025-021. https://www.mitsubishielectric.com/psirt/vulnerability/pdf/2025-021_en.pdf ",
          "product_ids": [
            "CSAFPID-0002"
          ],
          "url": "https://www.mitsubishielectric.com/psirt/vulnerability/pdf/2025-021_en.pdf"
        }
      ],
      "scores": [
        {
          "cvss_v3": {
            "attackComplexity": "LOW",
            "attackVector": "NETWORK",
            "availabilityImpact": "HIGH",
            "baseScore": 7.5,
            "baseSeverity": "HIGH",
            "confidentialityImpact": "NONE",
            "integrityImpact": "NONE",
            "privilegesRequired": "NONE",
            "scope": "UNCHANGED",
            "userInteraction": "NONE",
            "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H",
            "version": "3.1"
          },
          "products": [
            "CSAFPID-0002"
          ]
        }
      ]
    }
  ]
}


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Author Source Type Date

Nomenclature

  • Seen: The vulnerability was mentioned, discussed, or observed by the user.
  • Confirmed: The vulnerability has been validated from an analyst's perspective.
  • Published Proof of Concept: A public proof of concept is available for this vulnerability.
  • Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
  • Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
  • Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
  • Not confirmed: The user expressed doubt about the validity of the vulnerability.
  • Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.



Detection rules are retrieved from Rulezet.