CVE-2021-0239
In Juniper Networks Junos OS Evolved, receipt of a stream of specific genuine Layer 2 frames may cause the Advanced Forwarding Toolkit (AFT) manager process (Evo-aftmand), responsible for handling Route, Class-of-Service (CoS), Firewall operations within the packet forwarding engine (PFE) to crash and restart, leading to a Denial of Service (DoS) condition. By continuously sending this specific stream of genuine Layer 2 frames, an attacker can repeatedly crash the PFE, causing a sustained Denial of Service (DoS). This issue affects Juniper Networks Junos OS Evolved: All versions prior to 20.4R1-EVO. This issue does not affect Junos OS versions.
CVSS
- Versión: 3.1
- Vector: CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
- Puntuación base: 6.5
Probabilidad de explotación (EPSS)
- Probabilidad de explotación en los próximos 30 días: 0.38%
- Percentil entre todas las CVEs puntuadas: 30
- Fecha de la puntuación: 7/10/2026
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-754
- CWE-754
Referencias
JSON original (NVD)
Mostrar
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"authentication": "NONE",
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"published": "2021-04-22T20:15:08.943",
"references": [
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"url": "https://kb.juniper.net/JSA11134",
"tags": [
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"source": "sirt@juniper.net"
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"descriptions": [
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"lang": "en",
"value": "In Juniper Networks Junos OS Evolved, receipt of a stream of specific genuine Layer 2 frames may cause the Advanced Forwarding Toolkit (AFT) manager process (Evo-aftmand), responsible for handling Route, Class-of-Service (CoS), Firewall operations within the packet forwarding engine (PFE) to crash and restart, leading to a Denial of Service (DoS) condition. By continuously sending this specific stream of genuine Layer 2 frames, an attacker can repeatedly crash the PFE, causing a sustained Denial of Service (DoS). This issue affects Juniper Networks Junos OS Evolved: All versions prior to 20.4R1-EVO. This issue does not affect Junos OS versions."
},
{
"lang": "es",
"value": "En Juniper Networks, Junos OS Evolved, la recepción de un flujo de tramas de capa 2 genuinas específicas puede causar que el proceso de gestión Advanced Forwarding Toolkit (AFT) (Evo-aftmand), responsable de gestionar las operaciones de ruta, clase de servicio (CoS) y cortafuegos. dentro del packet forwarding engine (PFE) para bloquearse y reiniciarse, conllevando a una condición de Denegación de Servicio (DoS). Al enviar continuamente este flujo específico de tramas genuinas de Capa 2, Un atacante puede ser capaz de bloquear repetidamente el PFE, provocando una Denegación de Servicio (DoS) sostenida. Este problema afecta a Juniper Networks Junos OS Evolved: todas las versiones anteriores a 20.4R1-EVO. Este problema no afecta a Junos OS versiones"
}
],
"lastModified": "2026-06-17T03:29:34.513",
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