{
  "id": "CVE-2021-29484",
  "sourceIdentifier": "security-advisories@github.com",
  "published": "2021-04-29T21:15:08.590",
  "lastModified": "2021-09-14T18:47:05.297",
  "vulnStatus": "Analyzed",
  "descriptions": [
    {
      "lang": "en",
      "value": "Ghost is a Node.js CMS. An unused endpoint added during the development of 4.0.0 has left sites vulnerable to untrusted users gaining access to Ghost Admin. Attackers can gain access by getting logged in users to click a link containing malicious code. Users do not need to enter credentials and may not know they've visited a malicious site. Ghost(Pro) has already been patched. We can find no evidence that the issue was exploited on Ghost(Pro) prior to the patch being added. Self-hosters are impacted if running Ghost a version between 4.0.0 and 4.3.2. Immediate action should be taken to secure your site. The issue has been fixed in 4.3.3, all 4.x sites should upgrade as soon as possible. As the endpoint is unused, the patch simply removes it. As a workaround blocking access to /ghost/preview can also mitigate the issue."
    },
    {
      "lang": "es",
      "value": "Ghost es un CMS Node.js. Un endpoint sin uso agregado durante el desarrollo de la versi\u00f3n 4.0.0 ha dejado los sitios vulnerables a que usuarios no confiables que obtienen acceso a Ghost Admin. Los atacantes pueden conseguir acceso al hacer que unos usuarios que tengan iniciada la sesi\u00f3n hagan clic en un enlace que contenga c\u00f3digo malicioso. Los usuarios no necesitan introducir sus credenciales y es posible que no sepan que han visitado un sitio malicioso. Ghost(Pro) ya ha sido parcheado. No hemos encontrado pruebas de que el problema se haya explotado en Ghost(Pro) antes de que se agregara el parche. Los  autohospedadores est\u00e1n afectados si ejecutan Ghost en una versi\u00f3n entre 4.0.0 y 4.3.2. Se deben tomar medidas inmediatas para proteger su sitio. El problema ha sido corregido en 4.3.3, todos los sitios 4.x deber\u00edan actualizarse lo antes posible. Como el endpoint sin uso, el parche simplemente lo elimina. Como soluci\u00f3n alternativa, bloquear el acceso a /ghost/preview tambi\u00e9n puede mitigar el problema."
    }
  ],
  "metrics": {
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        "source": "security-advisories@github.com",
        "type": "Primary",
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          "version": "3.1",
          "vectorString": "CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:N",
          "attackVector": "NETWORK",
          "attackComplexity": "HIGH",
          "privilegesRequired": "NONE",
          "userInteraction": "REQUIRED",
          "scope": "UNCHANGED",
          "confidentialityImpact": "HIGH",
          "integrityImpact": "HIGH",
          "availabilityImpact": "NONE",
          "baseScore": 6.8,
          "baseSeverity": "MEDIUM"
        },
        "exploitabilityScore": 1.6,
        "impactScore": 5.2
      },
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        "source": "nvd@nist.gov",
        "type": "Secondary",
        "cvssData": {
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          "attackVector": "NETWORK",
          "attackComplexity": "LOW",
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          "scope": "CHANGED",
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          "integrityImpact": "LOW",
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      }
    ],
    "cvssMetricV2": [
      {
        "source": "nvd@nist.gov",
        "type": "Primary",
        "cvssData": {
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          "vectorString": "AV:N/AC:M/Au:N/C:N/I:P/A:N",
          "accessVector": "NETWORK",
          "accessComplexity": "MEDIUM",
          "authentication": "NONE",
          "confidentialityImpact": "NONE",
          "integrityImpact": "PARTIAL",
          "availabilityImpact": "NONE",
          "baseScore": 4.3
        },
        "baseSeverity": "MEDIUM",
        "exploitabilityScore": 8.6,
        "impactScore": 2.9,
        "acInsufInfo": false,
        "obtainAllPrivilege": false,
        "obtainUserPrivilege": false,
        "obtainOtherPrivilege": false,
        "userInteractionRequired": true
      }
    ]
  },
  "weaknesses": [
    {
      "source": "nvd@nist.gov",
      "type": "Primary",
      "description": [
        {
          "lang": "en",
          "value": "CWE-79"
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      "source": "security-advisories@github.com",
      "type": "Secondary",
      "description": [
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  "configurations": [
    {
      "nodes": [
        {
          "operator": "OR",
          "negate": false,
          "cpeMatch": [
            {
              "vulnerable": true,
              "criteria": "cpe:2.3:a:ghost:ghost:*:*:*:*:*:node.js:*:*",
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  "references": [
    {
      "url": "https://blog.sonarsource.com/ghost-admin-takeover",
      "source": "security-advisories@github.com",
      "tags": [
        "Exploit",
        "Third Party Advisory"
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    },
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      "url": "https://forum.ghost.org/t/critical-security-update-available-for-ghost-4-x/22290",
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      "url": "https://github.com/TryGhost/Ghost/security/advisories/GHSA-9fgx-q25h-jxrg",
      "source": "security-advisories@github.com",
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      "url": "https://www.npmjs.com/package/ghost",
      "source": "security-advisories@github.com",
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}