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CVE-2021-41095

Estado: ModificadaMedia (6.1)—

Discourse is an open source discussion platform. There is a cross-site scripting (XSS) vulnerability in versions 2.7.7 and earlier of the `stable` branch, versions 2.8.0.beta6 and earlier of the `beta` branch, and versions 2.8.0.beta6 and earlier of the `tests-passed` branch. Rendering of some error messages that contain user input can be susceptible to XSS attacks. This vulnerability only affects sites which have blocked watched words that contain HTML tags, modified or disabled Discourse's default Content Security Policy. This issue is patched in the latest `stable`, `beta` and `tests-passed` versions of Discourse. As a workaround, avoid modifying or disabling Discourse’s default Content Security Policy, and blocking watched words containing HTML tags.

CVSS

Probabilidad de explotación (EPSS)

EPSS (Exploit Prediction Scoring System, de FIRST) estima la probabilidad de que una vulnerabilidad sea explotada en 30 días. Complementa a CVSS (impacto) y a CISA KEV (explotación confirmada).

Tecnologías afectadas (1)

Discourse — Discourse

CWE

Referencias

JSON original (NVD)

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  "id": "CVE-2021-41095",
  "cveTags": [],
  "metrics": {
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        "type": "Primary",
        "source": "nvd@nist.gov",
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          "baseScore": 4.3,
          "accessVector": "NETWORK",
          "vectorString": "AV:N/AC:M/Au:N/C:N/I:P/A:N",
          "authentication": "NONE",
          "integrityImpact": "PARTIAL",
          "accessComplexity": "MEDIUM",
          "availabilityImpact": "NONE",
          "confidentialityImpact": "NONE"
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        "impactScore": 2.9,
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          "integrityImpact": "LOW",
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  "published": "2021-09-27T20:15:07.267",
  "references": [
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      "url": "https://github.com/discourse/discourse/pull/14434/commits/40b776b9d39c41d9273d01eecf8fe03aa39fcb59",
      "tags": [
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      "url": "https://github.com/discourse/discourse/security/advisories/GHSA-qvqx-2h7w-m479",
      "tags": [
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  "vulnStatus": "Modified",
  "weaknesses": [
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      "type": "Secondary",
      "source": "security-advisories@github.com",
      "description": [
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          "lang": "en",
          "value": "CWE-79"
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      "source": "nvd@nist.gov",
      "description": [
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          "value": "CWE-79"
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  ],
  "descriptions": [
    {
      "lang": "en",
      "value": "Discourse is an open source discussion platform. There is a cross-site scripting (XSS) vulnerability in versions 2.7.7 and earlier of the `stable` branch, versions 2.8.0.beta6 and earlier of the `beta` branch, and versions 2.8.0.beta6 and earlier of the `tests-passed` branch. Rendering of some error messages that contain user input can be susceptible to XSS attacks. This vulnerability only affects sites which have blocked watched words that contain HTML tags, modified or disabled Discourse's default Content Security Policy. This issue is patched in the latest `stable`, `beta` and `tests-passed` versions of Discourse. As a workaround, avoid modifying or disabling Discourse’s default Content Security Policy, and blocking watched words containing HTML tags."
    },
    {
      "lang": "es",
      "value": "Discourse es una plataforma de debate de código abierto. Se presenta una vulnerabilidad de tipo cross-site scripting (XSS) en versiones 2.7.7 y anteriores de la rama \"stable\", en las versiones 2.8.0.beta6 y anteriores de la rama \"beta\", y en las versiones 2.8.0.beta6 y anteriores de la rama \"tests-passed\". La representación de algunos mensajes de error que contienen entradas del usuario puede ser susceptible de ataques de tipo XSS. Esta vulnerabilidad sólo afecta a los sitios que han bloqueado las palabras vigiladas que contienen etiquetas HTML, han modificado o han deshabilitado la política de seguridad de contenidos predeterminada de Discourse. Este problema está parcheado en las últimas versiones \"stable\", \"beta\" y \"tests-passed\" de Discourse. Como solución, evite la modificar o desactivar la política de seguridad de contenidos predeterminada de Discourse y bloquear las palabras vigiladas que contengan etiquetas HTML"
    }
  ],
  "lastModified": "2026-06-17T04:07:51.933",
  "configurations": [
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