FKIE_CVE-2021-0287

Vulnerability from fkie_nvd - Published: 2021-07-15 20:15 - Updated: 2026-06-17 03:29
Severity
6.5 (Medium) - CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Summary
In a Segment Routing ISIS (SR-ISIS)/MPLS environment, on Juniper Networks Junos OS and Junos OS Evolved devices, configured with ISIS Flexible Algorithm for Segment Routing and sensor-based statistics, a flap of a ISIS link in the network, can lead to a routing process daemon (RPD) crash and restart, causing a Denial of Service (DoS). Continued link flaps will create a sustained Denial of Service (DoS) condition. This issue affects: Juniper Networks Junos OS: 19.4 versions prior to 19.4R1-S4, 19.4R3-S2; 20.1 versions prior to 20.1R2-S1, 20.1R3; 20.2 versions prior to 20.2R2-S2, 20.2R3; 20.3 versions prior to 20.3R2; Juniper Networks Junos OS Evolved: 20.3-EVO versions prior to 20.3R2-EVO; 20.4-EVO versions prior to 20.4R2-EVO. This issue does not affect: Juniper Networks Junos OS releases prior to 19.4R1. Juniper Networks Junos OS Evolved releases prior to 19.4R1-EVO.
References
sirt@juniper.nethttps://kb.juniper.net/JSA11189Vendor Advisory
af854a3a-2127-422b-91ae-364da2661108https://kb.juniper.net/JSA11189Vendor Advisory
Impacted products
Vendor Product Version
juniper junos 19.4
juniper junos 19.4
juniper junos 19.4
juniper junos 19.4
juniper junos 19.4
juniper junos 19.4
juniper junos 19.4
juniper junos 19.4
juniper junos 19.4
juniper junos 19.4
juniper junos 20.1
juniper junos 20.1
juniper junos 20.1
juniper junos 20.1
juniper junos 20.1
juniper junos 20.1
juniper junos 20.2
juniper junos 20.2
juniper junos 20.2
juniper junos 20.2
juniper junos 20.2
juniper junos 20.2
juniper junos 20.3
juniper junos 20.3
juniper junos_os_evolved 20.3
juniper junos_os_evolved 20.3
juniper junos_os_evolved 20.4
To clipboard 

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  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "In a Segment Routing ISIS (SR-ISIS)/MPLS environment, on Juniper Networks Junos OS and Junos OS Evolved devices, configured with ISIS Flexible Algorithm for Segment Routing and sensor-based statistics, a flap of a ISIS link in the network, can lead to a routing process daemon (RPD) crash and restart, causing a Denial of Service (DoS). Continued link flaps will create a sustained Denial of Service (DoS) condition. This issue affects: Juniper Networks Junos OS: 19.4 versions prior to 19.4R1-S4, 19.4R3-S2; 20.1 versions prior to 20.1R2-S1, 20.1R3; 20.2 versions prior to 20.2R2-S2, 20.2R3; 20.3 versions prior to 20.3R2; Juniper Networks Junos OS Evolved: 20.3-EVO versions prior to 20.3R2-EVO; 20.4-EVO versions prior to 20.4R2-EVO. This issue does not affect: Juniper Networks Junos OS releases prior to 19.4R1. Juniper Networks Junos OS Evolved releases prior to 19.4R1-EVO."
    },
    {
      "lang": "es",
      "value": "En un entorno de Enrutamiento por Segmentos ISIS (SR-ISIS)/MPLS, en los dispositivos Juniper Networks Junos OS y Junos OS Evolved, configurados con el Algoritmo Flexible ISIS para el Enrutamiento por Segmentos y las estad\u00edsticas basadas en sensores, un flap de un enlace ISIS en la red puede conllevar a el bloqueo y el reinicio de un demonio en el proceso de enrutamiento (RPD), causando una Denegaci\u00f3n de Servicio (DoS). Un continuo enlace en los flaps crear\u00e1 una condici\u00f3n de Denegaci\u00f3n de Servicio (DoS) sostenida. Este problema afecta a: Juniper Networks Junos OS: Versiones 19.4 anteriores a 19.4R1-S4, 19.4R3-S2; versiones 20.1 anteriores a 20.1R2-S1, 20.1R3; versiones 20.2 anteriores a 20.2R2-S2, 20.2R3; versiones 20.3 anteriores a 20.3R2; Juniper Networks Junos OS Evolved: versiones 20.3-EVO anteriores a 20.3R2-EVO; versiones 20.4-EVO anteriores a 20.4R2-EVO. Este problema no afecta a: Las versiones de Juniper Networks Junos OS anteriores a 19.4R1. Las versiones de Juniper Networks Junos OS Evolved anteriores a 19.4R1-EVO"
    }
  ],
  "id": "CVE-2021-0287",
  "lastModified": "2026-06-17T03:29:43.053",
  "metrics": {
    "cvssMetricV2": [
      {
        "acInsufInfo": false,
        "baseSeverity": "MEDIUM",
        "cvssData": {
          "accessComplexity": "MEDIUM",
          "accessVector": "ADJACENT_NETWORK",
          "authentication": "NONE",
          "availabilityImpact": "COMPLETE",
          "baseScore": 5.7,
          "confidentialityImpact": "NONE",
          "integrityImpact": "NONE",
          "vectorString": "AV:A/AC:M/Au:N/C:N/I:N/A:C",
          "version": "2.0"
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        "exploitabilityScore": 5.5,
        "impactScore": 6.9,
        "obtainAllPrivilege": false,
        "obtainOtherPrivilege": false,
        "obtainUserPrivilege": false,
        "source": "nvd@nist.gov",
        "type": "Primary",
        "userInteractionRequired": false
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    "cvssMetricV31": [
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          "attackVector": "ADJACENT_NETWORK",
          "availabilityImpact": "HIGH",
          "baseScore": 6.5,
          "baseSeverity": "MEDIUM",
          "confidentialityImpact": "NONE",
          "integrityImpact": "NONE",
          "privilegesRequired": "NONE",
          "scope": "UNCHANGED",
          "userInteraction": "NONE",
          "vectorString": "CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H",
          "version": "3.1"
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        "exploitabilityScore": 2.8,
        "impactScore": 3.6,
        "source": "sirt@juniper.net",
        "type": "Secondary"
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  },
  "published": "2021-07-15T20:15:10.413",
  "references": [
    {
      "source": "sirt@juniper.net",
      "tags": [
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      "url": "https://kb.juniper.net/JSA11189"
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  "vulnStatus": "Modified",
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          "value": "CWE-754"
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      ],
      "source": "nvd@nist.gov",
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}



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