CVE-2021-39220
Estado: ModificadaBaja (3.5)—
Nextcloud is an open-source, self-hosted productivity platform The Nextcloud Mail application prior to versions 1.10.4 and 1.11.0 does by default not render images in emails to not leak the read state or user IP. The privacy filter failed to filter images with a relative protocol. It is recommended that the Nextcloud Mail application is upgraded to 1.10.4 or 1.11.0. There are no known workarounds aside from upgrading.
CVSS
- Versión: 3.1
- Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:L/I:N/A:N
- Puntuación base: 3.5
Probabilidad de explotación (EPSS)
- Probabilidad de explotación en los próximos 30 días: 0.78%
- Percentil entre todas las CVEs puntuadas: 55
- Fecha de la puntuación: 6/10/2026
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)
CWE
- CWE-20, CWE-200
- CWE-20
Referencias
- https://github.com/nextcloud/mail/pull/5470
- https://github.com/nextcloud/security-advisories/security/advisories/GHSA-6q9v-wm8r-rcv5
- https://hackerone.com/reports/1308147
- https://github.com/nextcloud/mail/pull/5470
- https://github.com/nextcloud/security-advisories/security/advisories/GHSA-6q9v-wm8r-rcv5
- https://hackerone.com/reports/1308147
JSON original (NVD)
Mostrar
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"id": "CVE-2021-39220",
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"vectorString": "AV:N/AC:M/Au:S/C:P/I:N/A:N",
"authentication": "SINGLE",
"integrityImpact": "NONE",
"accessComplexity": "MEDIUM",
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"confidentialityImpact": "PARTIAL"
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},
{
"lang": "es",
"value": "Nextcloud es una plataforma de productividad de código abierto y auto-alojada La aplicación Nextcloud Mail versiones anteriores a 1.10.4 y 1.11.0, no renderiza por defecto las imágenes en los correos electrónicos para no filtrar el estado de lectura o la IP del usuario. El filtro de privacidad no filtraba las imágenes con un protocolo relativo. Es recomendado actualizar la aplicación Nextcloud Mail a la versión 1.10.4 o 1.11.0. No se presentan soluciones conocidas aparte de la actualización"
}
],
"lastModified": "2026-06-17T04:03:20.413",
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