NCSC-2026-0041

Vulnerability from csaf_ncscnl - Published: 2026-01-28 09:32 - Updated: 2026-01-28 09:32
Summary
Kwetsbaarheid verholpen in Fortinet producten

Notes

The Netherlands Cyber Security Center (henceforth: NCSC-NL) maintains this page to enhance access to its information and security advisories. The use of this security advisory is subject to the following terms and conditions: NCSC-NL makes every reasonable effort to ensure that the content of this page is kept up to date, and that it is accurate and complete. Nevertheless, NCSC-NL cannot entirely rule out the possibility of errors, and therefore cannot give any warranty in respect of its completeness, accuracy or continuous keeping up-to-date. The information contained in this security advisory is intended solely for the purpose of providing general information to professional users. No rights can be derived from the information provided therein. NCSC-NL and the Kingdom of the Netherlands assume no legal liability or responsibility for any damage resulting from either the use or inability of use of this security advisory. This includes damage resulting from the inaccuracy of incompleteness of the information contained in the advisory. This security advisory is subject to Dutch law. All disputes related to or arising from the use of this advisory will be submitted to the competent court in The Hague. This choice of means also applies to the court in summary proceedings.
Feiten
Fortinet heeft een kwetsbaarheid verholpen in FortiAnalyzer, FortiManager, FortiOS en FortiProxy producten.
Interpretaties
De kwetsbaarheid bevindt zich in specifieke implementaties van FortiCloud SSO-authenticatie. De kwetsbaarheid stelt aanvallers met een geregistreerd apparaat en een FortiCloud-account in staat om de authenticatie te omzeilen en toegang te krijgen tot andere geregistreerde apparaten wanneer FortiCloud SSO-authenticatie is ingeschakeld. Fortinet heeft aangegeven dat er actief misbruik van de kwetsbaarheid is waargenomen. Fortinet heeft in hun advisory ook indicators-of-compromise (IoC's) beschikbaar gesteld om misbruik van de kwetsbaarheid te onderkennen. Het NCSC adviseert partijen die gebruikmaken van de kwetsbare implementaties om ook middels deze IoC’s terug te kijken in de logging.
Oplossingen
Fortinet heeft updates uitgebracht om de kwetsbaarheden te verhelpen. Zie bijgevoegde referenties voor meer informatie.
Kans
high
Schade
high
CWE-288
Authentication Bypass Using an Alternate Path or Channel
To clipboard 

{
  "document": {
    "category": "csaf_security_advisory",
    "csaf_version": "2.0",
    "distribution": {
      "tlp": {
        "label": "WHITE"
      }
    },
    "lang": "nl",
    "notes": [
      {
        "category": "legal_disclaimer",
        "text": "The Netherlands Cyber Security Center (henceforth: NCSC-NL) maintains this page to enhance access to its information and security advisories. The use of this security advisory is subject to the following terms and conditions:\n\n    NCSC-NL makes every reasonable effort to ensure that the content of this page is kept up to date, and that it is accurate and complete. Nevertheless, NCSC-NL cannot entirely rule out the possibility of errors, and therefore cannot give any warranty in respect of its completeness, accuracy or continuous keeping up-to-date. The information contained in this security advisory is intended solely for the purpose of providing general information to professional users. No rights can be derived from the information provided therein.\n\n    NCSC-NL and the Kingdom of the Netherlands assume no legal liability or responsibility for any damage resulting from either the use or inability of use of this security advisory. This includes damage resulting from the inaccuracy of incompleteness of the information contained in the advisory.\n    This security advisory is subject to Dutch law. All disputes related to or arising from the use of this advisory will be submitted to the competent court in The Hague. This choice of means also applies to the court in summary proceedings."
      },
      {
        "category": "description",
        "text": "Fortinet heeft een kwetsbaarheid verholpen in FortiAnalyzer, FortiManager, FortiOS en FortiProxy producten.",
        "title": "Feiten"
      },
      {
        "category": "description",
        "text": "De kwetsbaarheid bevindt zich in specifieke implementaties van FortiCloud SSO-authenticatie. De kwetsbaarheid stelt aanvallers met een geregistreerd apparaat en een FortiCloud-account in staat om de authenticatie te omzeilen en toegang te krijgen tot andere geregistreerde apparaten wanneer FortiCloud SSO-authenticatie is ingeschakeld. \n\nFortinet heeft aangegeven dat er actief misbruik van de kwetsbaarheid is waargenomen. Fortinet heeft in hun advisory ook indicators-of-compromise (IoC\u0027s) beschikbaar gesteld om misbruik van de kwetsbaarheid te onderkennen. Het NCSC adviseert partijen die gebruikmaken van de kwetsbare implementaties om ook middels deze IoC\u2019s terug te kijken in de logging.",
        "title": "Interpretaties"
      },
      {
        "category": "description",
        "text": "Fortinet heeft updates uitgebracht om de kwetsbaarheden te verhelpen. Zie bijgevoegde referenties voor meer informatie.",
        "title": "Oplossingen"
      },
      {
        "category": "general",
        "text": "high",
        "title": "Kans"
      },
      {
        "category": "general",
        "text": "high",
        "title": "Schade"
      },
      {
        "category": "general",
        "text": "Authentication Bypass Using an Alternate Path or Channel",
        "title": "CWE-288"
      }
    ],
    "publisher": {
      "category": "coordinator",
      "contact_details": "cert@ncsc.nl",
      "name": "Nationaal Cyber Security Centrum",
      "namespace": "https://www.ncsc.nl/"
    },
    "references": [
      {
        "category": "external",
        "summary": "Reference",
        "url": "https://www.fortiguard.com/psirt/FG-IR-26-060"
      },
      {
        "category": "external",
        "summary": "Reference",
        "url": "https://www.fortinet.com/blog/psirt-blogs/analysis-of-sso-abuse-on-fortios"
      }
    ],
    "title": "Kwetsbaarheid verholpen in Fortinet producten",
    "tracking": {
      "current_release_date": "2026-01-28T09:32:41.752905Z",
      "generator": {
        "date": "2025-08-04T16:30:00Z",
        "engine": {
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      "revision_history": [
        {
          "date": "2026-01-28T09:32:41.752905Z",
          "number": "1.0.0",
          "summary": "Initiele versie"
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      ],
      "status": "final",
      "version": "1.0.0"
    }
  },
  "product_tree": {
    "branches": [
      {
        "branches": [
          {
            "branches": [
              {
                "category": "product_version_range",
                "name": "vers:unknown/*",
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                  "name": "vers:unknown/*",
                  "product_id": "CSAFPID-1"
                }
              }
            ],
            "category": "product_name",
            "name": "FortiAnalyzer"
          },
          {
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          {
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        ],
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  "vulnerabilities": [
    {
      "cve": "CVE-2026-24858",
      "cwe": {
        "id": "CWE-288",
        "name": "Authentication Bypass Using an Alternate Path or Channel"
      },
      "notes": [
        {
          "category": "other",
          "text": "Authentication Bypass Using an Alternate Path or Channel",
          "title": "CWE-288"
        },
        {
          "category": "description",
          "text": "A vulnerability in Fortinet\u0027s FortiAnalyzer, FortiManager, and FortiOS allows attackers with FortiCloud accounts to bypass authentication, leading to unauthorized access to registered devices when FortiCloud SSO is enabled.",
          "title": "Summary"
        }
      ],
      "product_status": {
        "known_affected": [
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          "CSAFPID-2",
          "CSAFPID-3",
          "CSAFPID-4"
        ]
      },
      "references": [
        {
          "category": "self",
          "summary": "CVE-2026-24858 | NCSC-NL Website",
          "url": "https://vulnerabilities.ncsc.nl/csaf/v2/2026/cve-2026-24858.json"
        }
      ],
      "scores": [
        {
          "cvss_v3": {
            "baseScore": 9.8,
            "baseSeverity": "CRITICAL",
            "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H/E:H/RL:O/RC:C",
            "version": "3.1"
          },
          "products": [
            "CSAFPID-1",
            "CSAFPID-2",
            "CSAFPID-3",
            "CSAFPID-4"
          ]
        }
      ],
      "title": "CVE-2026-24858"
    }
  ]
}


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