{
  "schemaVersion": 1,
  "attribution": [
    {
      "source": "CISA Known Exploited Vulnerabilities",
      "url": "https://www.cisa.gov/known-exploited-vulnerabilities-catalog",
      "licence": "US government work"
    },
    {
      "source": "GitHub Advisory Database",
      "url": "https://github.com/advisories",
      "licence": "CC BY 4.0"
    },
    {
      "source": "Have I Been Pwned",
      "url": "https://haveibeenpwned.com/",
      "licence": "CC BY 4.0"
    },
    {
      "source": "CVE Program (CVE records)",
      "url": "https://www.cve.org/Legal/TermsOfUse",
      "licence": "CVE Terms of Use",
      "notice": "Copyright © 1999-2026, The MITRE Corporation. CVE is a trademark and the CVE logo is a registered trademark of The MITRE Corporation.",
      "terms": "CVE Usage: MITRE hereby grants you a perpetual, worldwide, non-exclusive, no-charge, royalty-free, irrevocable copyright license to reproduce, prepare derivative works of, publicly display, publicly perform, sublicense, and distribute Common Vulnerabilities and Exposures (CVE™). Any copy you make for such purposes is authorized provided that you reproduce MITRE's copyright designation and this license in any such copy."
    },
    {
      "source": "FIRST EPSS",
      "url": "https://www.first.org/epss/",
      "licence": "free to use; FIRST requests attribution"
    }
  ],
  "record": {
    "id": "CVE-2021-31379",
    "sourceURL": "https://www.cve.org/CVERecord?id=CVE-2021-31379",
    "idYear": 2021,
    "status": "PUBLISHED",
    "publishedAt": "2021-10-19T18:17:19.849Z",
    "updatedAt": "2024-09-16T22:56:51.495Z",
    "importedAt": "2026-10-24T01:56:32.228Z",
    "snapshot": {
      "id": "cve_2026-10-24_midnight_baseline",
      "at": "2026-10-24T00:00:00.000Z",
      "source": "https://github.com/CVEProject/cvelistV5/releases/tag/cve_2026-10-24_0100Z"
    },
    "facts": {
      "title": "Junos OS: MX Series: MPC 7/8/9/10/11 cards with MAP-E: PFE halts when an attacker sends malformed IPv4 or IPv6 traffic inside the MAP-E tunnel.",
      "summary": "An Incorrect Behavior Order vulnerability in the MAP-E automatic tunneling mechanism of Juniper Networks Junos OS allows an attacker to send certain malformed IPv4 or IPv6 packets to cause a Denial of Service (DoS) to the PFE on the device which is disabled as a result of the processing of these packets. Continued receipt and processing of these malformed IPv4 or IPv6 packets will create a sustained Denial of Service (DoS) condition. This issue only affects MPC 7/8/9/10/11 cards, when MAP-E IP reassembly is enabled on these cards. An indicator of compromise is the output: FPC [\"FPC ID\" # e.g. \"0\"] PFE #{PFE ID # e.g. \"1\"] : Fabric Disabled Example: FPC 0 PFE #1 : Fabric Disabled when using the command: show chassis fabric fpcs An example of a healthy result of the command use would be: user@device-re1> show chassis fabric fpcs Fabric management FPC state: FPC 0 PFE #0 Plane 0: Plane enabled Plane 1: Plane enabled Plane 2: Plane enabled Plane 3: Plane enabled Plane 4: Plane enabled Plane 5: Plane enabled Plane 6: Plane enabled Plane 7: Plane enabled This issue affects: Juniper Networks Junos OS on MX Series with MPC 7/8/9/10/11 cards, when MAP-E IP reassembly is enabled on these cards. 17.2 version 17.2R1 and later versions; 17.3 versions prior to 17.3R3-S9; 17.4 versions prior to 17.4R2-S12, 17.4R3-S3; 18.1 versions prior to 18.1R3-S11; 18.2 versions prior to 18.2R2-S6, 18.2R3-S3; 18.3 versions prior to 18.3R2-S4, 18.3R3-S1; 18.4 versions prior to 18.4R1-S8, 18.4R2-S5, 18.4R3; 19.1 versions prior to 19.1R1-S6, 19.1R2-S2, 19.1R3; 19.2 versions prior to 19.2R1-S5, 19.2R2; 19.3 versions prior to 19.3R2-S5, 19.3R3. This issue does not affect Juniper Networks Junos OS versions prior to 17.2R1.",
      "affected": [
        {
          "vendor": "Juniper Networks",
          "product": "Junos OS",
          "platforms": [
            "MX Series"
          ],
          "versions": [
            {
              "version": "unspecified",
              "status": "unaffected",
              "versionType": "custom",
              "lessThan": "17.2R1"
            },
            {
              "version": "17.2R1",
              "status": "affected",
              "versionType": "custom",
              "lessThan": "17.2*"
            },
            {
              "version": "17.3",
              "status": "affected",
              "versionType": "custom",
              "lessThan": "17.3R3-S9"
            },
            {
              "version": "17.4",
              "status": "affected",
              "versionType": "custom",
              "lessThan": "17.4R2-S12, 17.4R3-S3"
            },
            {
              "version": "18.1",
              "status": "affected",
              "versionType": "custom",
              "lessThan": "18.1R3-S11"
            },
            {
              "version": "18.2",
              "status": "affected",
              "versionType": "custom",
              "lessThan": "18.2R2-S6, 18.2R3-S3"
            },
            {
              "version": "18.3",
              "status": "affected",
              "versionType": "custom",
              "lessThan": "18.3R2-S4, 18.3R3-S1"
            },
            {
              "version": "18.4",
              "status": "affected",
              "versionType": "custom",
              "lessThan": "18.4R1-S8, 18.4R2-S5, 18.4R3"
            },
            {
              "version": "19.1",
              "status": "affected",
              "versionType": "custom",
              "lessThan": "19.1R1-S6, 19.1R2-S2, 19.1R3"
            },
            {
              "version": "19.2",
              "status": "affected",
              "versionType": "custom",
              "lessThan": "19.2R1-S5, 19.2R2"
            },
            {
              "version": "19.3",
              "status": "affected",
              "versionType": "custom",
              "lessThan": "19.3R2-S5, 19.3R3"
            }
          ]
        }
      ]
    }
  }
}