{"schemaVersion":3,"id":"CVE-2021-1586","aliases":[],"status":"published","duplicateOf":null,"title":null,"description":"A vulnerability in the Multi-Pod or Multi-Site network configurations for Cisco Nexus 9000 Series Fabric Switches in Application Centric Infrastructure (ACI) mode could allow an unauthenticated, remote attacker to unexpectedly restart the device, resulting in a denial of service (DoS) condition. This vulnerability exists because TCP traffic sent to a specific port on an affected device is not properly sanitized. An attacker could exploit this vulnerability by sending crafted TCP data to a specific port that is listening on a public-facing IP address for the Multi-Pod or Multi-Site configuration. A successful exploit could allow the attacker to cause the device to restart unexpectedly, resulting in a DoS condition.","dates":{"published":"2021-08-25T19:10:59.639Z","modified":"2024-11-07T22:02:32.217Z","reserved":null,"kevAdded":[],"kevDue":[]},"cvss":{"headline":{"score":8.6,"severity":"high","version":"3.1","versionLabel":"v3.1","source":"CVE.org","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:H","computed":false,"selection":"backend-summary"},"metrics":[{"version":"3.1","versionLabel":"v3.1","source":"CVE.org","score":8.6,"severity":"high","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:H","exploitability":null,"impact":null,"computed":false},{"version":"3.1","versionLabel":"v3.1","source":"NVD","score":8.6,"severity":"high","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:H","exploitability":null,"impact":null,"computed":false},{"version":"2.0","versionLabel":"v2.0","source":"NVD","score":5,"severity":"medium","vector":"AV:N/AC:L/Au:N/C:N/I:N/A:P","exploitability":null,"impact":null,"computed":false}]},"epss":{"probability":0.02453,"percentile":0.84163,"severity":"low","asOf":"2026-10-19T00:00:00.000Z","change":{"pp":0,"baselineDate":"2026-09-19T00:00:00.000Z","baselineScore":0.02453},"history":[{"date":"2026-09-14T00:00:00.000Z","score":0.02453,"percentile":null},{"date":"2026-09-15T00:00:00.000Z","score":0.02453,"percentile":null},{"date":"2026-09-16T00:00:00.000Z","score":0.02453,"percentile":null},{"date":"2026-09-17T00:00:00.000Z","score":0.02453,"percentile":null},{"date":"2026-09-18T00:00:00.000Z","score":0.02453,"percentile":null},{"date":"2026-09-19T00:00:00.000Z","score":0.02453,"percentile":null},{"date":"2026-09-20T00:00:00.000Z","score":0.02453,"percentile":null},{"date":"2026-09-21T00:00:00.000Z","score":0.02453,"percentile":null},{"date":"2026-09-22T00:00:00.000Z","score":0.02453,"percentile":null},{"date":"2026-09-23T00:00:00.000Z","score":0.02453,"percentile":null},{"date":"2026-09-24T00:00:00.000Z","score":0.02453,"percentile":null},{"date":"2026-09-25T00:00:00.000Z","score":0.02453,"percentile":null},{"date":"2026-09-26T00:00:00.000Z","score":0.02453,"percentile":null},{"date":"2026-09-27T00:00:00.000Z","score":0.02453,"percentile":null},{"date":"2026-09-28T00:00:00.000Z","score":0.02453,"percentile":null},{"date":"2026-09-29T00:00:00.000Z","score":0.02453,"percentile":null},{"date":"2026-09-30T00:00:00.000Z","score":0.02453,"percentile":null},{"date":"2026-10-01T00:00:00.000Z","score":0.02453,"percentile":null},{"date":"2026-10-02T00:00:00.000Z","score":0.02453,"percentile":null},{"date":"2026-10-03T00:00:00.000Z","score":0.02453,"percentile":null},{"date":"2026-10-04T00:00:00.000Z","score":0.02453,"percentile":null},{"date":"2026-10-05T00:00:00.000Z","score":0.02453,"percentile":null},{"date":"2026-10-06T00:00:00.000Z","score":0.02453,"percentile":null},{"date":"2026-10-07T00:00:00.000Z","score":0.02453,"percentile":null},{"date":"2026-10-08T00:00:00.000Z","score":0.02453,"percentile":null},{"date":"2026-10-09T00:00:00.000Z","score":0.02453,"percentile":null},{"date":"2026-10-10T00:00:00.000Z","score":0.02453,"percentile":null},{"date":"2026-10-11T00:00:00.000Z","score":0.02453,"percentile":null},{"date":"2026-10-12T00:00:00.000Z","score":0.02453,"percentile":null},{"date":"2026-10-13T00:00:00.000Z","score":0.02453,"percentile":null},{"date":"2026-10-14T00:00:00.000Z","score":0.02453,"percentile":null},{"date":"2026-10-15T00:00:00.000Z","score":0.02453,"percentile":null},{"date":"2026-10-16T00:00:00.000Z","score":0.02453,"percentile":null},{"date":"2026-10-17T00:00:00.000Z","score":0.02453,"percentile":null},{"date":"2026-10-18T00:00:00.000Z","score":0.02453,"percentile":null},{"date":"2026-10-19T00:00:00.000Z","score":0.02453,"percentile":0.84163}],"last30":[{"date":"2026-09-19T00:00:00.000Z","score":0.02453,"percentile":null},{"date":"2026-09-20T00:00:00.000Z","score":0.02453,"percentile":null},{"date":"2026-09-21T00:00:00.000Z","score":0.02453,"percentile":null},{"date":"2026-09-22T00:00:00.000Z","score":0.02453,"percentile":null},{"date":"2026-09-23T00:00:00.000Z","score":0.02453,"percentile":null},{"date":"2026-09-24T00:00:00.000Z","score":0.02453,"percentile":null},{"date":"2026-09-25T00:00:00.000Z","score":0.02453,"percentile":null},{"date":"2026-09-26T00:00:00.000Z","score":0.02453,"percentile":null},{"date":"2026-09-27T00:00:00.000Z","score":0.02453,"percentile":null},{"date":"2026-09-28T00:00:00.000Z","score":0.02453,"percentile":null},{"date":"2026-09-29T00:00:00.000Z","score":0.02453,"percentile":null},{"date":"2026-09-30T00:00:00.000Z","score":0.02453,"percentile":null},{"date":"2026-10-01T00:00:00.000Z","score":0.02453,"percentile":null},{"date":"2026-10-02T00:00:00.000Z","score":0.02453,"percentile":null},{"date":"2026-10-03T00:00:00.000Z","score":0.02453,"percentile":null},{"date":"2026-10-04T00:00:00.000Z","score":0.02453,"percentile":null},{"date":"2026-10-05T00:00:00.000Z","score":0.02453,"percentile":null},{"date":"2026-10-06T00:00:00.000Z","score":0.02453,"percentile":null},{"date":"2026-10-07T00:00:00.000Z","score":0.02453,"percentile":null},{"date":"2026-10-08T00:00:00.000Z","score":0.02453,"percentile":null},{"date":"2026-10-09T00:00:00.000Z","score":0.02453,"percentile":null},{"date":"2026-10-10T00:00:00.000Z","score":0.02453,"percentile":null},{"date":"2026-10-11T00:00:00.000Z","score":0.02453,"percentile":null},{"date":"2026-10-12T00:00:00.000Z","score":0.02453,"percentile":null},{"date":"2026-10-13T00:00:00.000Z","score":0.02453,"percentile":null},{"date":"2026-10-14T00:00:00.000Z","score":0.02453,"percentile":null},{"date":"2026-10-15T00:00:00.000Z","score":0.02453,"percentile":null},{"date":"2026-10-16T00:00:00.000Z","score":0.02453,"percentile":null},{"date":"2026-10-17T00:00:00.000Z","score":0.02453,"percentile":null},{"date":"2026-10-18T00:00:00.000Z","score":0.02453,"percentile":null},{"date":"2026-10-19T00:00:00.000Z","score":0.02453,"percentile":0.84163}]},"kev":{"state":"not-listed","entries":[],"listedCount":0,"totalCatalogs":3,"catalogs":[{"source":"cisa","label":"CISA","listed":false,"entry":null},{"source":"enisa","label":"ENISA","listed":false,"entry":null},{"source":"circl","label":"CIRCL","listed":false,"entry":null}]},"ransomware":{"state":"none-recorded","sources":[]},"exploits":[],"exploitCount":0,"weaknesses":[{"id":"CWE-345","name":"Insufficient Verification of Data Authenticity","description":"The product does not sufficiently verify the origin or authenticity of data, in a way that causes it to accept invalid data.","type":"weakness","status":"Draft","abstraction":"Class","likelihoodOfExploit":null,"url":"https://cwe.mitre.org/data/definitions/345.html"}],"affected":[{"vendor":"cisco","product":"cisco nx-os system software in aci mode","name":"Cisco NX-OS System Software in ACI Mode","label":"cisco nx-os system software in aci mode","ecosystem":null,"cpePart":"a","purl":null,"purlType":null,"versions":[{"text":"n/a","noFixRecorded":false,"fixedIn":null}],"versionsText":"n/a","eol":null,"hubHref":"/vendor/cisco/cisco_nx-os_system_software_in_aci_mode"},{"vendor":"cisco","product":"nx-os","name":"NX-OS","label":"nx-os","ecosystem":null,"cpePart":"o","purl":null,"purlType":null,"versions":[{"text":"15.0\\(2e\\)","noFixRecorded":false,"fixedIn":null},{"text":"15.1\\(1h\\)","noFixRecorded":false,"fixedIn":null}],"versionsText":"15.0\\(2e\\) | 15.1\\(1h\\)","eol":null,"hubHref":"/vendor/cisco/nx-os"}],"affectedCount":2,"eol":{"hasEol":false,"count":0},"references":[{"url":"https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-n9kaci-tcp-dos-YXukt6gM","label":"tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-n9kaci-tcp-dos-YXukt6gM","hostname":"tools.cisco.com","tags":["Vendor Advisory","X Refsource CISCO","Patch"]}],"lineage":{"upstream":[],"downstream":[],"duplicates":[],"related":[]},"timeline":[{"kind":"published","date":"2021-08-25T19:10:59.639Z","label":"Published","detail":"Vulnerability first disclosed.","source":null},{"kind":"modified","date":"2024-11-07T22:02:32.217Z","label":"Last modified","detail":"Vulnerability information updated.","source":null}],"risk":{"score":35,"level":"medium","profile":"Default","thresholds":{"critical":75,"high":50,"medium":25,"low":10}},"meta":{"dataAsOf":"2026-10-19T21:10:56.077Z","stale":false,"partial":false}}