CVE-2019-16216
Zulip server before 2.0.5 incompletely validated the MIME types of uploaded files. A user who is logged into the server could upload files of certain types to mount a stored cross-site scripting attack on other logged-in users. On a Zulip server using the default local uploads backend, the attack is only effective against browsers lacking support for Content-Security-Policy such as Internet Explorer 11. On a Zulip server using the S3 uploads backend, the attack is confined to the origin of the configured S3 uploads hostname and cannot reach the Zulip server itself.
CVSS
- Versión: 3.1
- Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N
- Puntuación base: 5.4
Probabilidad de explotación (EPSS)
- Probabilidad de explotación en los próximos 30 días: 0.68%
- Percentil entre todas las CVEs puntuadas: 51
- 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-79
Referencias
JSON original (NVD)
Mostrar
{
"id": "CVE-2019-16216",
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"affected": [
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"published": "2019-09-18T12:15:10.990",
"references": [
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"value": "Zulip server before 2.0.5 incompletely validated the MIME types of uploaded files. A user who is logged into the server could upload files of certain types to mount a stored cross-site scripting attack on other logged-in users. On a Zulip server using the default local uploads backend, the attack is only effective against browsers lacking support for Content-Security-Policy such as Internet Explorer 11. On a Zulip server using the S3 uploads backend, the attack is confined to the origin of the configured S3 uploads hostname and cannot reach the Zulip server itself."
},
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"value": "El servidor Zulip versiones anteriores a 2.0.5, validó de manera incompleta los tipos MIME de archivos cargados. Un usuario que haya iniciado sesión en el servidor podría cargar archivos de ciertos tipos para montar un ataque de tipo cross-site scripting almacenado sobre otros usuarios registrados. En un servidor Zulip que usa el backend de carga local predeterminado, el ataque solo es efectivo contra los navegadores que carecen de soporte para Content-Security-Policy como Internet Explorer versión 11. En un servidor Zulip usando el backend de carga S3, el ataque es confinado en el origen del hostname de carga S3 configurado y no puede alcanzar al servidor Zulip en sí."
}
],
"lastModified": "2026-06-17T02:21:54.840",
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