{
  "id": "CVE-2020-3566",
  "url": "https://spydr.io/cve/CVE-2020-3566",
  "published": "2020-08-29T16:15:09.797Z",
  "modified": "2026-06-17T03:18:36.940Z",
  "score": 8.6,
  "severity": "high",
  "cvss_version": "3.1",
  "vector": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:H",
  "score_source": "NVD",
  "epss": 0.03702,
  "epss_percentile": 0.89438,
  "exploited": true,
  "kev": {
    "added": "2021-11-03",
    "due": "2022-05-03",
    "action": "Apply updates per vendor instructions.",
    "ransomware": "Unknown",
    "name": "Cisco IOS XR Software DVMRP Memory Exhaustion Vulnerability",
    "notes": "https://nvd.nist.gov/vuln/detail/CVE-2020-3566"
  },
  "ssvc_exploitation": "active",
  "vendors": [
    "Cisco"
  ],
  "products": [
    "Cisco IOS XR Software"
  ],
  "cwes": [
    "CWE-400",
    "CWE-770"
  ],
  "description": "A vulnerability in the Distance Vector Multicast Routing Protocol (DVMRP) feature of Cisco IOS XR Software could allow an unauthenticated, remote attacker to exhaust process memory of an affected device. The vulnerability is due to insufficient queue management for Internet Group Management Protocol (IGMP) packets. An attacker could exploit this vulnerability by sending crafted IGMP traffic to an affected device. A successful exploit could allow the attacker to cause memory exhaustion, resulting in instability of other processes. These processes may include, but are not limited to, interior and exterior routing protocols. Cisco will release software updates that address this vulnerability.",
  "status": "Analyzed",
  "score_type": "Primary",
  "scores": {
    "cvss_v40": null,
    "cvss_v31": 8.6,
    "cvss_v30": null
  },
  "references": [
    {
      "url": "https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-iosxr-dvmrp-memexh-dSmpdvfz",
      "tags": [
        "Vendor Advisory"
      ]
    },
    {
      "url": "https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2020-3566",
      "tags": [
        "US Government Resource"
      ]
    }
  ],
  "nvd_url": "https://nvd.nist.gov/vuln/detail/CVE-2020-3566",
  "covered_in": [],
  "attribution": [
    {
      "source": "NVD",
      "url": "https://nvd.nist.gov",
      "notice": "This product uses data from the NVD API but is not endorsed or certified by the NVD."
    },
    {
      "source": "CISA KEV",
      "url": "https://www.cisa.gov/known-exploited-vulnerabilities-catalog",
      "notice": "Known exploited vulnerabilities from the CISA KEV catalog."
    },
    {
      "source": "FIRST EPSS",
      "url": "https://www.first.org/epss",
      "notice": "Exploit prediction scores from FIRST EPSS."
    }
  ]
}