FKIE_CVE-2026-31833

Vulnerability from fkie_nvd - Published: 2026-03-10 22:16 - Updated: 2026-03-18 20:01
Severity ?
6.7 (Medium) - CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:L
Summary
Umbraco is an ASP.NET CMS. From 16.2.0 to before 16.5.1 and 17.2.2, An authenticated backoffice user with access to Settings can inject malicious HTML into property type descriptions. Due to an overly permissive attributeNameCheck configuration (/.+/) in the UFM DOMPurify instance, event handler attributes such as onclick and onload, when used within Umbraco web components (umb-*, uui-*, ufm-*) were not filtered. This vulnerability is fixed in 16.5.1 and 17.2.2.
References
security-advisories@github.comhttps://github.com/umbraco/Umbraco-CMS/security/advisories/GHSA-vrqc-59mw-qqg7Vendor Advisory
Impacted products
Vendor Product Version
umbraco umbraco_cms *
umbraco umbraco_cms *
To clipboard 

{
  "configurations": [
    {
      "nodes": [
        {
          "cpeMatch": [
            {
              "criteria": "cpe:2.3:a:umbraco:umbraco_cms:*:*:*:*:*:*:*:*",
              "matchCriteriaId": "2BB33F17-782C-4F7C-AC48-CC05C1B1886D",
              "versionEndExcluding": "16.5.1",
              "versionStartIncluding": "16.2.0",
              "vulnerable": true
            },
            {
              "criteria": "cpe:2.3:a:umbraco:umbraco_cms:*:*:*:*:*:*:*:*",
              "matchCriteriaId": "7C8D4B05-B561-4CDB-8B2A-BD734F9E9A74",
              "versionEndExcluding": "17.2.2",
              "versionStartIncluding": "17.0.0",
              "vulnerable": true
            }
          ],
          "negate": false,
          "operator": "OR"
        }
      ]
    }
  ],
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "Umbraco is an ASP.NET CMS. From 16.2.0 to before 16.5.1 and 17.2.2, An authenticated backoffice user with access to Settings can inject malicious HTML into property type descriptions. Due to an overly permissive attributeNameCheck configuration (/.+/) in the UFM DOMPurify instance, event handler attributes such as onclick and onload, when used within Umbraco web components (umb-*, uui-*, ufm-*) were not filtered. This vulnerability is fixed in 16.5.1 and 17.2.2."
    },
    {
      "lang": "es",
      "value": "Umbraco es un CMS de ASP.NET. Desde la versi\u00f3n 16.2.0 hasta antes de la 16.5.1 y la 17.2.2, un usuario autenticado del backoffice con acceso a Settings puede inyectar HTML malicioso en las descripciones de tipos de propiedades. Debido a una configuraci\u00f3n de attributeNameCheck (/.+/) excesivamente permisiva en la instancia de DOMPurify de UFM, los atributos de gestor de eventos como onclick y onload, cuando se usaban dentro de componentes web de Umbraco (umb-*, uui-*, ufm-*), no se filtraban. Esta vulnerabilidad est\u00e1 corregida en las versiones 16.5.1 y 17.2.2."
    }
  ],
  "id": "CVE-2026-31833",
  "lastModified": "2026-03-18T20:01:24.743",
  "metrics": {
    "cvssMetricV31": [
      {
        "cvssData": {
          "attackComplexity": "LOW",
          "attackVector": "NETWORK",
          "availabilityImpact": "LOW",
          "baseScore": 6.7,
          "baseSeverity": "MEDIUM",
          "confidentialityImpact": "HIGH",
          "integrityImpact": "HIGH",
          "privilegesRequired": "HIGH",
          "scope": "UNCHANGED",
          "userInteraction": "NONE",
          "vectorString": "CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:L",
          "version": "3.1"
        },
        "exploitabilityScore": 1.2,
        "impactScore": 5.5,
        "source": "security-advisories@github.com",
        "type": "Secondary"
      }
    ]
  },
  "published": "2026-03-10T22:16:21.410",
  "references": [
    {
      "source": "security-advisories@github.com",
      "tags": [
        "Vendor Advisory"
      ],
      "url": "https://github.com/umbraco/Umbraco-CMS/security/advisories/GHSA-vrqc-59mw-qqg7"
    }
  ],
  "sourceIdentifier": "security-advisories@github.com",
  "vulnStatus": "Analyzed",
  "weaknesses": [
    {
      "description": [
        {
          "lang": "en",
          "value": "CWE-79"
        }
      ],
      "source": "security-advisories@github.com",
      "type": "Primary"
    }
  ]
}


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