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CVE-2021-39195

Status: ModifiedMedium (6.5)—

Misskey is an open source, decentralized microblogging platform. In affected versions a Server-Side Request Forgery vulnerability exists in "Upload from URL" and remote attachment handling. This could result in the disclosure of non-public information within the internal network. This has been fixed in 12.90.0. However, if you are using a proxy, you will need to take additional measures. As a workaround this exploit may be avoided by appropriately restricting access to private networks from the host where the application is running.

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).

Affected technologies (1)

Misskey — Misskey

CWEs

References

Raw JSON (NVD)

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{
  "id": "CVE-2021-39195",
  "cveTags": [],
  "metrics": {
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  "vulnStatus": "Modified",
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      "description": [
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      "lang": "en",
      "value": "Misskey is an open source, decentralized microblogging platform. In affected versions a Server-Side Request Forgery vulnerability exists in \"Upload from URL\" and remote attachment handling. This could result in the disclosure of non-public information within the internal network. This has been fixed in 12.90.0. However, if you are using a proxy, you will need to take additional measures. As a workaround this exploit may be avoided by appropriately restricting access to private networks from the host where the application is running."
    },
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      "lang": "es",
      "value": "Misskey es una plataforma de microblogging descentralizada de código abierto. En las versiones afectadas se presenta una vulnerabilidad de tipo Server-Side Request Forgery en el manejo de \"Upload from URL\" y archivos adjuntos remotos. Esto podría resultar en una divulgación de información no pública dentro de la red interna. Esto es corregido en versión 12.90.0. Sin embargo, si esta usando un proxy, necesitará tomar medidas adicionales. Como solución alternativa, este problema puede ser  evitado restringiendo apropiadamente el acceso a las redes privadas desde el host donde se ejecuta la aplicación"
    }
  ],
  "lastModified": "2026-06-17T04:03:17.353",
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