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CVE-2020-5811

Status: ModifiedMedium (6.5)—💥 Exploit

An authenticated path traversal vulnerability exists during package installation in Umbraco CMS <= 8.9.1 or current, which could result in arbitrary files being written outside of the site home and expected paths when installing an Umbraco package.

CVSS

Exploitation probability (EPSS)

EPSS (Exploit Prediction Scoring System, FIRST) estimates how likely a vulnerability is to be exploited in the wild within 30 days. It complements CVSS (impact) and CISA KEV (confirmed exploitation).

💥 Public exploits

Exploit code or detection templates are publicly available. This is not the same as confirmed active exploitation (KEV), but it raises the risk: patch with priority.

Affected technologies (1)

Umbraco — Umbraco CMS

CWEs

References

Raw JSON (NVD)

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{
  "id": "CVE-2020-5811",
  "cveTags": [],
  "metrics": {
    "cvssMetricV2": [
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        "type": "Primary",
        "source": "nvd@nist.gov",
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          "accessVector": "NETWORK",
          "vectorString": "AV:N/AC:L/Au:S/C:N/I:P/A:N",
          "authentication": "SINGLE",
          "integrityImpact": "PARTIAL",
          "accessComplexity": "LOW",
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          "confidentialityImpact": "NONE"
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          "vectorString": "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:N",
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  "affected": [
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      "affectedData": [
        {
          "vendor": "n/a",
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  "published": "2020-12-30T16:15:12.447",
  "references": [
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      "source": "af854a3a-2127-422b-91ae-364da2661108"
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  "vulnStatus": "Modified",
  "weaknesses": [
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      "source": "nvd@nist.gov",
      "description": [
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          "value": "CWE-22"
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      "lang": "en",
      "value": "An authenticated path traversal vulnerability exists during package installation in Umbraco CMS <= 8.9.1 or current, which could result in arbitrary files being written outside of the site home and expected paths when installing an Umbraco package."
    },
    {
      "lang": "es",
      "value": "Se presenta una vulnerabilidad de salto de ruta autenticada durante la instalación del paquete en Umbraco CMS versiones anteriores a 8.9.1 o actual, lo que podría resultar en la escritura de archivos arbitrarios fuera del inicio del sitio y las rutas esperadas cuando se instala un paquete Umbraco."
    }
  ],
  "lastModified": "2026-06-17T03:22:16.790",
  "configurations": [
    {
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