NCSC-2026-0395

Vulnerability from csaf_ncscnl - Published: 2026-09-30 14:43 - Updated: 2026-09-30 14:43
Summary
Kwetsbaarheid verholpen in Cisco Catalyst SD-WAN Manager
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: Cisco heeft een kwetsbaarheid verholpen in Cisco Catalyst SD-WAN Manager.
Interpretaties: De kwetsbaarheid bevindt zich in een API van Cisco Catalyst SD-WAN Manager. Door onjuiste verwerking van URI-encoding kunnen ongeauthenticeerde kwaadwillenden authenticatiemechanismen omzeilen. Hierdoor kan de kwaadwillende administratieve toegang tot het systeem verkrijgen en de controle over het systeem overnemen.
Oplossingen: Cisco heeft updates uitgebracht om de kwetsbaarheid te verhelpen. Ook heeft Cisco indicators-of-comrpomise (IOC's) gedeeld. Het NCSC adviseert organisaties met klem om SD-WAN Manager-systemen op aanwezigheid van deze IOC's te controleren alvorens de beveiligingsupdates te installeren. Zie de bijgevoegde referentie voor meer informatie.
Kans: medium
Schade: high
CWE-177: Improper Handling of URL Encoding (Hex Encoding)
CVE-2026-76504

A vulnerability in Cisco Catalyst SD-WAN Manager's API session authentication allows unauthenticated remote attackers to bypass authentication via improper URI encoding, potentially granting admin-level access.

9.8 (Critical)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
CWE-177 - Improper Handling of URL Encoding (Hex Encoding)
Affected products
Product Identifier Version Remediation
vers:unknown/*
Cisco / Catalyst SD-WAN Manager
 vers:unknown/*
References
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": "Cisco heeft een kwetsbaarheid verholpen in Cisco Catalyst SD-WAN Manager.",
        "title": "Feiten"
      },
      {
        "category": "description",
        "text": "De kwetsbaarheid bevindt zich in een API van Cisco Catalyst SD-WAN Manager. Door onjuiste verwerking van URI-encoding kunnen ongeauthenticeerde kwaadwillenden authenticatiemechanismen omzeilen. Hierdoor kan de kwaadwillende administratieve toegang tot het systeem verkrijgen en de controle over het systeem overnemen.",
        "title": "Interpretaties"
      },
      {
        "category": "description",
        "text": "Cisco heeft updates uitgebracht om de kwetsbaarheid te verhelpen. Ook heeft Cisco indicators-of-comrpomise (IOC\u0027s) gedeeld. Het NCSC adviseert organisaties met klem om SD-WAN Manager-systemen op aanwezigheid van deze IOC\u0027s te controleren alvorens de beveiligingsupdates te installeren.\n\nZie de bijgevoegde referentie voor meer informatie.",
        "title": "Oplossingen"
      },
      {
        "category": "general",
        "text": "medium",
        "title": "Kans"
      },
      {
        "category": "general",
        "text": "high",
        "title": "Schade"
      },
      {
        "category": "general",
        "text": "Improper Handling of URL Encoding (Hex Encoding)",
        "title": "CWE-177"
      }
    ],
    "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://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-sdwan-webauth-xr8beuuU"
      }
    ],
    "title": "Kwetsbaarheid verholpen in Cisco Catalyst SD-WAN Manager",
    "tracking": {
      "current_release_date": "2026-09-30T14:43:36.844848Z",
      "generator": {
        "date": "2025-08-04T16:30:00Z",
        "engine": {
          "name": "V.A.",
          "version": "1.3"
        }
      },
      "id": "NCSC-2026-0395",
      "initial_release_date": "2026-09-30T14:43:36.844848Z",
      "revision_history": [
        {
          "date": "2026-09-30T14:43:36.844848Z",
          "number": "1.0.0",
          "summary": "Initiele versie"
        }
      ],
      "status": "final",
      "version": "1.0.0"
    }
  },
  "product_tree": {
    "branches": [
      {
        "branches": [
          {
            "branches": [
              {
                "category": "product_version_range",
                "name": "vers:unknown/*",
                "product": {
                  "name": "vers:unknown/*",
                  "product_id": "CSAFPID-1"
                }
              }
            ],
            "category": "product_name",
            "name": "Catalyst SD-WAN Manager"
          }
        ],
        "category": "vendor",
        "name": "Cisco"
      }
    ]
  },
  "vulnerabilities": [
    {
      "cve": "CVE-2026-76504",
      "cwe": {
        "id": "CWE-177",
        "name": "Improper Handling of URL Encoding (Hex Encoding)"
      },
      "notes": [
        {
          "category": "other",
          "text": "Improper Handling of URL Encoding (Hex Encoding)",
          "title": "CWE-177"
        },
        {
          "category": "description",
          "text": "A vulnerability in Cisco Catalyst SD-WAN Manager\u0027s API session authentication allows unauthenticated remote attackers to bypass authentication via improper URI encoding, potentially granting admin-level access.",
          "title": "Summary"
        }
      ],
      "product_status": {
        "known_affected": [
          "CSAFPID-1"
        ]
      },
      "references": [
        {
          "category": "self",
          "summary": "CVE-2026-76504 | NCSC-NL Website",
          "url": "https://vulnerabilities.ncsc.nl/csaf/v2/2026/cve-2026-76504.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",
            "version": "3.1"
          },
          "products": [
            "CSAFPID-1"
          ]
        }
      ],
      "title": "CVE-2026-76504"
    }
  ]
}



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