CVE-2019-9749
Estado: ModificadaAlta (7.5)—
An issue was discovered in the MQTT input plugin in Fluent Bit through 1.0.4. When this plugin acts as an MQTT broker (server), it mishandles incoming network messages. After processing a crafted packet, the plugin's mqtt_packet_drop function (in /plugins/in_mqtt/mqtt_prot.c) executes the memmove() function with a negative size parameter. That leads to a crash of the whole Fluent Bit server via a SIGSEGV signal.
CVSS
- Versión: 3.1
- Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
- Puntuación base: 7.5
Probabilidad de explotación (EPSS)
- Probabilidad de explotación en los próximos 30 días: 1.66%
- Percentil entre todas las CVEs puntuadas: 76
- 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-681
Referencias
JSON original (NVD)
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"published": "2019-03-13T19:29:00.297",
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},
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"lang": "es",
"value": "Se ha descubierto un problema en el plugin de entradas MQTT en Fluent Bit hasta la CVErsión 1.0.4. Cuando este plugin actúa como broker MQTT (servidor), gestiona de manera incorrecta los mensajes de red entrantes. Tras procesar un paquete manipulado, la función del plugin mqtt_packet_drop (en /plugins/in_mqtt/mqtt_prot.c) ejecuta la función memmoCVE() con un parámetro de tamaño negativo. Esto conduce a un cierre inesperado de todo el servidor Fluent Bit mediante una señal SIGSEGV."
}
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"lastModified": "2026-06-17T02:44:16.890",
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