{"id":"CVE-2020-3120","aliases":["EUVD-2020-24391","GHSA-vw86-rxwf-9vhm"],"status":"published","title":"Cisco FXOS, IOS XR, and NX-OS Software Cisco Discovery Protocol Denial of Service Vulnerability","description":"A vulnerability in the Cisco Discovery Protocol implementation for Cisco FXOS Software, Cisco IOS XR Software, and Cisco NX-OS Software could allow an unauthenticated, adjacent attacker to cause a reload of an affected device, resulting in a denial of service (DoS) condition. The vulnerability is due to a missing check when the affected software processes Cisco Discovery Protocol messages. An attacker could exploit this vulnerability by sending a malicious Cisco Discovery Protocol packet to an affected device. A successful exploit could allow the attacker to exhaust system memory, causing the device to reload. Cisco Discovery Protocol is a Layer 2 protocol. To exploit this vulnerability, an attacker must be in the same broadcast domain as the affected device (Layer 2 adjacent).","severity":{"version":"3.0","score":7.4,"vector":"CVSS:3.0/AV:A/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:H","level":"high","assessor":"cna","from":"cve"},"epss":{"day":"2026-11-11","score":0.01639,"percentile":0.76672,"model":"v2026.06.15"},"facts":{"in_kev":false,"known_exploited":false,"public_exploit":false,"fix_available":false},"cwes":["CWE-190"],"published":"2020-02-05T17:50:18Z","modified":"2026-06-17T03:17:23Z","products":[{"vendor":"cisco","product":"cisco ios xr software"},{"vendor":"cisco","product":"firepower_extensible_operating_system"},{"vendor":"cisco","product":"fxos"},{"vendor":"cisco","product":"ios_xr"},{"vendor":"cisco","product":"nx-os"},{"vendor":"cisco","product":"ucs_manager"}],"references":[{"url":"https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20200205-fxnxos-iosxr-cdp-dos","tags":["vendor-advisory","x_refsource_CISCO","x_transferred","Vendor Advisory"]},{"url":"http://packetstormsecurity.com/files/156203/Cisco-Discovery-Protocol-CDP-Remote-Device-Takeover.html","tags":["x_refsource_MISC","x_transferred","Third Party Advisory","VDB Entry"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2020-3120"},{"url":"https://github.com/advisories/GHSA-vw86-rxwf-9vhm"}],"sources":{"cve":[{"id":"CVE-2020-3120","title":"Cisco FXOS, IOS XR, and NX-OS Software Cisco Discovery Protocol Denial of Service Vulnerability","description":"A vulnerability in the Cisco Discovery Protocol implementation for Cisco FXOS Software, Cisco IOS XR Software, and Cisco NX-OS Software could allow an unauthenticated, adjacent attacker to cause a reload of an affected device, resulting in a denial of service (DoS) condition. The vulnerability is due to a missing check when the affected software processes Cisco Discovery Protocol messages. An attacker could exploit this vulnerability by sending a malicious Cisco Discovery Protocol packet to an affected device. A successful exploit could allow the attacker to exhaust system memory, causing the device to reload. Cisco Discovery Protocol is a Layer 2 protocol. To exploit this vulnerability, an attacker must be in the same broadcast domain as the affected device (Layer 2 adjacent).","status":"published","published":"2020-02-05T17:50:18.427Z","modified":"2024-11-15T17:42:14.893Z","cvss":[{"version":"3.0","score":7.4,"vector":"CVSS:3.0/AV:A/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:H","level":"high","assessor":"cna"}],"cwes":["CWE-190"],"updated_at":"2026-11-02T14:35:51.923913Z"}],"euvd":[{"id":"EUVD-2020-24391","description":"A vulnerability in the Cisco Discovery Protocol implementation for Cisco FXOS Software, Cisco IOS XR Software, and Cisco NX-OS Software could allow an unauthenticated, adjacent attacker to cause a reload of an affected device, resulting in a denial of service (DoS) condition. The vulnerability is due to a missing check when the affected software processes Cisco Discovery Protocol messages. An attacker could exploit this vulnerability by sending a malicious Cisco Discovery Protocol packet to an affected device. A successful exploit could allow the attacker to exhaust system memory, causing the device to reload. Cisco Discovery Protocol is a Layer 2 protocol. To exploit this vulnerability, an attacker must be in the same broadcast domain as the affected device (Layer 2 adjacent).","status":"published","published":"2020-02-05T17:50:18Z","modified":"2024-11-15T17:42:14Z","cvss":[{"version":"3.0","score":7.4,"vector":"CVSS:3.0/AV:A/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:H","level":"high"}],"updated_at":"2026-11-03T00:04:58.605338Z"}],"ghsa":[{"id":"GHSA-vw86-rxwf-9vhm","title":"A vulnerability in the Cisco Discovery Protocol implementation for Cisco FXOS Software, Cisco IOS...","description":"A vulnerability in the Cisco Discovery Protocol implementation for Cisco FXOS Software, Cisco IOS XR Software, and Cisco NX-OS Software could allow an unauthenticated, adjacent attacker to cause a reload of an affected device, resulting in a denial of service (DoS) condition. The vulnerability is due to a missing check when the affected software processes Cisco Discovery Protocol messages. An attacker could exploit this vulnerability by sending a malicious Cisco Discovery Protocol packet to an affected device. A successful exploit could allow the attacker to exhaust system memory, causing the device to reload. Cisco Discovery Protocol is a Layer 2 protocol. To exploit this vulnerability, an attacker must be in the same broadcast domain as the affected device (Layer 2 adjacent).","status":"published","published":"2022-05-24T17:08:03Z","modified":"2023-04-28T05:08:58Z","cvss":[{"version":"3.1","score":6.5,"vector":"CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H","level":"medium"}],"cwes":["CWE-190"],"updated_at":"2026-11-02T14:54:33.975596Z"}],"nvd":[{"id":"CVE-2020-3120","description":"A vulnerability in the Cisco Discovery Protocol implementation for Cisco FXOS Software, Cisco IOS XR Software, and Cisco NX-OS Software could allow an unauthenticated, adjacent attacker to cause a reload of an affected device, resulting in a denial of service (DoS) condition. The vulnerability is due to a missing check when the affected software processes Cisco Discovery Protocol messages. An attacker could exploit this vulnerability by sending a malicious Cisco Discovery Protocol packet to an affected device. A successful exploit could allow the attacker to exhaust system memory, causing the device to reload. Cisco Discovery Protocol is a Layer 2 protocol. To exploit this vulnerability, an attacker must be in the same broadcast domain as the affected device (Layer 2 adjacent).","status":"published","published":"2020-02-05T18:15:11.063Z","modified":"2026-06-17T03:17:23.383Z","cvss":[{"version":"3.1","score":6.5,"vector":"CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H","level":"medium","assessor":"primary"},{"version":"3.0","score":7.4,"vector":"CVSS:3.0/AV:A/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:H","level":"high","assessor":"secondary"},{"version":"2.0","score":6.1,"vector":"AV:A/AC:L/Au:N/C:N/I:N/A:C","level":"medium","assessor":"primary"}],"cwes":["CWE-190"],"updated_at":"2026-11-02T14:05:53.837808Z"}]}}