FKIE_CVE-2021-31363
Vulnerability from fkie_nvd - Published: 2021-10-19 19:15 - Updated: 2026-06-17 03:51
Severity
Summary
In an MPLS P2MP environment a Loop with Unreachable Exit Condition vulnerability in the routing protocol daemon (RPD) of Juniper Networks Junos OS and Junos OS Evolved allows an unauthenticated adjacent attacker to cause high load on RPD which in turn may lead to routing protocol flaps. If a system with sensor-based-stats enabled receives a specific LDP FEC this can lead to the above condition. Continued receipted of such an LDP FEC will create a sustained Denial of Service (DoS) condition. This issue affects: Juniper Networks Junos OS 19.2 version 19.2R2 and later versions prior to 19.2R3-S3; 19.3 versions prior to 19.3R2-S6, 19.3R3-S2; 19.4 versions prior to 19.4R1-S4, 19.4R2-S4, 19.4R3-S2; 20.1 versions prior to 20.1R2-S1, 20.1R3; 20.2 versions prior to 20.2R2-S1, 20.2R3; 20.3 versions prior to 20.3R1-S2, 20.3R2. This issue does not affect Juniper Networks Junos OS versions prior to 19.2R2. Juniper Networks Junos OS Evolved All versions prior to 20.1R2-S3-EVO; 20.3 versions prior to 20.3R1-S2-EVO.
References
| URL | Tags | ||
|---|---|---|---|
| sirt@juniper.net | https://kb.juniper.net/JSA11225 | Patch, Vendor Advisory | |
| af854a3a-2127-422b-91ae-364da2661108 | https://kb.juniper.net/JSA11225 | Patch, Vendor Advisory |
Impacted products
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"cveTags": [],
"descriptions": [
{
"lang": "en",
"value": "In an MPLS P2MP environment a Loop with Unreachable Exit Condition vulnerability in the routing protocol daemon (RPD) of Juniper Networks Junos OS and Junos OS Evolved allows an unauthenticated adjacent attacker to cause high load on RPD which in turn may lead to routing protocol flaps. If a system with sensor-based-stats enabled receives a specific LDP FEC this can lead to the above condition. Continued receipted of such an LDP FEC will create a sustained Denial of Service (DoS) condition. This issue affects: Juniper Networks Junos OS 19.2 version 19.2R2 and later versions prior to 19.2R3-S3; 19.3 versions prior to 19.3R2-S6, 19.3R3-S2; 19.4 versions prior to 19.4R1-S4, 19.4R2-S4, 19.4R3-S2; 20.1 versions prior to 20.1R2-S1, 20.1R3; 20.2 versions prior to 20.2R2-S1, 20.2R3; 20.3 versions prior to 20.3R1-S2, 20.3R2. This issue does not affect Juniper Networks Junos OS versions prior to 19.2R2. Juniper Networks Junos OS Evolved All versions prior to 20.1R2-S3-EVO; 20.3 versions prior to 20.3R1-S2-EVO."
},
{
"lang": "es",
"value": "En un entorno MPLS P2MP, una vulnerabilidad de bucle con condici\u00f3n de salida no alcanzable en el demonio del protocolo de enrutamiento (RPD) de Juniper Networks Junos OS y Junos OS Evolved permite a un atacante adyacente no autenticado causar una alta carga en el RPD, lo que a su vez puede conllevar a interrupciones del protocolo de enrutamiento. Si un sistema con las estad\u00edsticas basadas en sensores habilitadas recibe un LDP FEC espec\u00edfico, esto puede conllevar a una condici\u00f3n anterior. Una recepci\u00f3n continuada de tal LDP FEC crear\u00e1 una condici\u00f3n de Denegaci\u00f3n de Servicio (DoS) sostenida. Este problema afecta: Juniper Networks Junos OS 19.2 versi\u00f3n 19.2R2 y versiones posteriores anteriores a 19.2R3-S3; versiones 19.3 anteriores a 19.3R2-S6, 19.3R3-S2; versiones 19.4 anteriores a 19. 4R1-S4, 19.4R2-S4, 19.4R3-S2; versiones 20.1 anteriores a 20.1R2-S1, 20.1R3; versiones 20.2 anteriores a 20.2R2-S1, 20.2R3; versiones 20.3 anteriores a 20.3R1-S2, 20.3R2. Este problema no afecta a las versiones de Juniper Networks Junos OS anteriores a 19.2R2. Juniper Networks Junos OS Evolved Todas las versiones anteriores a 20.1R2-S3-EVO; versiones 20.3 anteriores a 20.3R1-S2-EVO"
}
],
"id": "CVE-2021-31363",
"lastModified": "2026-06-17T03:51:38.020",
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"baseScore": 6.5,
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Browse all ATT&CK techniques and the vulnerabilities related to each.
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