{
  "id": "CVE-2021-39338",
  "sourceIdentifier": "security@wordfence.com",
  "published": "2021-10-15T13:15:07.893",
  "lastModified": "2021-10-20T15:38:57.337",
  "vulnStatus": "Analyzed",
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "The MyBB Cross-Poster WordPress plugin is vulnerable to Stored Cross-Site Scripting due to insufficient input validation and sanitization via several parameters found in the ~/classes/MyBBXPSettings.php file which allowed attackers with administrative user access to inject arbitrary web scripts, in versions up to and including 1.0. This affects multi-site installations where unfiltered_html is disabled for administrators, and sites where unfiltered_html is disabled."
    },
    {
      "lang": "es",
      "value": "El plugin MyBB Cross-Poster de WordPress es vulnerable a un ataque de tipo Cross-Site Scripting Almacenado debido a una comprobaci\u00f3n insuficiente y saneamiento de entradas por medio de diversos par\u00e1metros encontrados en el archivo ~/classes/MyBBXPSettings.php que permit\u00edan a atacantes con acceso de usuario administrativo inyectar scripts web arbitrarios, en versiones hasta la 1.0 incluy\u00e9ndola. Esto afecta a las instalaciones multi-sitio en las que unfiltered_html est\u00e1 deshabilitado para los administradores, y a los sitios en los que unfiltered_html est\u00e1 deshabilitado"
    }
  ],
  "metrics": {
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      {
        "source": "nvd@nist.gov",
        "type": "Primary",
        "cvssData": {
          "version": "3.1",
          "vectorString": "CVSS:3.1/AV:N/AC:L/PR:H/UI:R/S:C/C:L/I:L/A:N",
          "attackVector": "NETWORK",
          "attackComplexity": "LOW",
          "privilegesRequired": "HIGH",
          "userInteraction": "REQUIRED",
          "scope": "CHANGED",
          "confidentialityImpact": "LOW",
          "integrityImpact": "LOW",
          "availabilityImpact": "NONE",
          "baseScore": 4.8,
          "baseSeverity": "MEDIUM"
        },
        "exploitabilityScore": 1.7,
        "impactScore": 2.7
      },
      {
        "source": "security@wordfence.com",
        "type": "Secondary",
        "cvssData": {
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          "vectorString": "CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:C/C:L/I:L/A:N",
          "attackVector": "NETWORK",
          "attackComplexity": "LOW",
          "privilegesRequired": "HIGH",
          "userInteraction": "NONE",
          "scope": "CHANGED",
          "confidentialityImpact": "LOW",
          "integrityImpact": "LOW",
          "availabilityImpact": "NONE",
          "baseScore": 5.5,
          "baseSeverity": "MEDIUM"
        },
        "exploitabilityScore": 2.3,
        "impactScore": 2.7
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    ],
    "cvssMetricV2": [
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        "source": "nvd@nist.gov",
        "type": "Primary",
        "cvssData": {
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          "vectorString": "AV:N/AC:H/Au:S/C:N/I:P/A:N",
          "accessVector": "NETWORK",
          "accessComplexity": "HIGH",
          "authentication": "SINGLE",
          "confidentialityImpact": "NONE",
          "integrityImpact": "PARTIAL",
          "availabilityImpact": "NONE",
          "baseScore": 2.1
        },
        "baseSeverity": "LOW",
        "exploitabilityScore": 3.9,
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        "acInsufInfo": false,
        "obtainAllPrivilege": false,
        "obtainUserPrivilege": false,
        "obtainOtherPrivilege": false,
        "userInteractionRequired": true
      }
    ]
  },
  "weaknesses": [
    {
      "source": "security@wordfence.com",
      "type": "Primary",
      "description": [
        {
          "lang": "en",
          "value": "CWE-79"
        }
      ]
    }
  ],
  "configurations": [
    {
      "nodes": [
        {
          "operator": "OR",
          "negate": false,
          "cpeMatch": [
            {
              "vulnerable": true,
              "criteria": "cpe:2.3:a:mybb_cross-poster_project:mybb_cross-poster:*:*:*:*:*:wordpress:*:*",
              "versionEndIncluding": "1.0",
              "matchCriteriaId": "82E70ADB-8194-4094-A15E-B10503ADC43F"
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  "references": [
    {
      "url": "https://github.com/BigTiger2020/word-press/blob/main/MyBB%20Cross-Poster.md",
      "source": "security@wordfence.com",
      "tags": [
        "Exploit",
        "Third Party Advisory"
      ]
    },
    {
      "url": "https://plugins.trac.wordpress.org/browser/mybb-cross-poster/trunk/classes/MyBBXPSettings.php",
      "source": "security@wordfence.com",
      "tags": [
        "Patch",
        "Third Party Advisory"
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    },
    {
      "url": "https://www.wordfence.com/vulnerability-advisories/#CVE-2021-39338",
      "source": "security@wordfence.com",
      "tags": [
        "Third Party Advisory"
      ]
    }
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}