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CVE-2021-34741

Estado: ModificadaAlta (7.5)—

A vulnerability in the email scanning algorithm of Cisco AsyncOS software for Cisco Email Security Appliance (ESA) could allow an unauthenticated, remote attacker to perform a denial of service (DoS) attack against an affected device. This vulnerability is due to insufficient input validation of incoming emails. An attacker could exploit this vulnerability by sending a crafted email through Cisco ESA. A successful exploit could allow the attacker to exhaust all the available CPU resources on an affected device for an extended period of time, preventing other emails from being processed and resulting in a DoS condition.

CVSS

Probabilidad de explotación (EPSS)

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)

Cisco — Asyncos

CWE

Referencias

JSON original (NVD)

Mostrar
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      "value": "Una vulnerabilidad en el algoritmo de análisis del correo electrónico del software Cisco AsyncOS para Cisco Email Security Appliance (ESA) podría permitir a un atacante remoto no autenticado llevar a cabo un ataque de denegación de servicio (DoS) contra un dispositivo afectado. Esta vulnerabilidad es debido a que la comprobación de entrada de los correos electrónicos entrantes es insuficiente. Un atacante podría explotar esta vulnerabilidad mediante el envío de un correo electrónico diseñado mediante Cisco ESA. Una explotación con éxito podría permitir al atacante agotar todos los recursos de CPU disponibles en un dispositivo afectado durante un período prolongado de tiempo, impidiendo que otros correos electrónicos sean procesados y dando lugar a una condición de DoS"
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