{"schemaVersion":3,"id":"CVE-2026-73437","aliases":[],"status":"published","duplicateOf":null,"title":null,"description":"On affected platforms running Arista EOS with Dynamic Host Configuration Protocol (DHCP) relay configured, an unauthenticated attacker with network access could send a crafted DHCP reply packet from an IP address that is not configured as a helper address, and the relay agent would forward it to clients without validating the source. This could allow the attacker to supply clients with malicious network configuration parameters, potentially resulting in traffic interception or denial of service for affected clients.","dates":{"published":"2026-09-15T21:02:49.314Z","modified":"2026-09-17T03:57:04.541Z","reserved":null,"kevAdded":[],"kevDue":[]},"cvss":{"headline":{"score":9.6,"severity":"critical","version":"3.1","versionLabel":"v3.1","source":"CVE.org","vector":"CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H","computed":false,"selection":"backend-summary"},"metrics":[{"version":"4.0","versionLabel":"v4.0","source":"CVE.org","score":6.5,"severity":"medium","vector":"CVSS:4.0/AV:A/AC:L/AT:N/PR:N/UI:N/VC:N/VI:L/VA:N/SC:H/SI:H/SA:H","exploitability":null,"impact":null,"computed":false},{"version":"3.1","versionLabel":"v3.1","source":"CVE.org","score":9.6,"severity":"critical","vector":"CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H","exploitability":null,"impact":null,"computed":false},{"version":"4.0","versionLabel":"v4.0","source":"NVD","score":6.5,"severity":"medium","vector":"CVSS:4.0/AV:A/AC:L/AT:N/PR:N/UI:N/VC:N/VI:L/VA:N/SC:H/SI:H/SA:H/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X","exploitability":null,"impact":null,"computed":false},{"version":"3.1","versionLabel":"v3.1","source":"NVD","score":9.6,"severity":"critical","vector":"CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H","exploitability":null,"impact":null,"computed":false}]},"epss":{"probability":0.00207,"percentile":0.1021,"severity":"low","asOf":"2026-10-20T00:00:00.000Z","change":{"pp":0.010999999999999985,"baselineDate":"2026-09-20T00:00:00.000Z","baselineScore":0.00196},"history":[{"date":"2026-09-16T00:00:00.000Z","score":0.00196,"percentile":null},{"date":"2026-09-17T00:00:00.000Z","score":0.00196,"percentile":null},{"date":"2026-09-18T00:00:00.000Z","score":0.00196,"percentile":null},{"date":"2026-09-19T00:00:00.000Z","score":0.00196,"percentile":null},{"date":"2026-09-20T00:00:00.000Z","score":0.00196,"percentile":null},{"date":"2026-09-21T00:00:00.000Z","score":0.00196,"percentile":null},{"date":"2026-09-22T00:00:00.000Z","score":0.00196,"percentile":null},{"date":"2026-09-23T00:00:00.000Z","score":0.00196,"percentile":null},{"date":"2026-09-24T00:00:00.000Z","score":0.00207,"percentile":null},{"date":"2026-09-25T00:00:00.000Z","score":0.00207,"percentile":null},{"date":"2026-09-26T00:00:00.000Z","score":0.00207,"percentile":null},{"date":"2026-09-27T00:00:00.000Z","score":0.00207,"percentile":null},{"date":"2026-09-28T00:00:00.000Z","score":0.00207,"percentile":null},{"date":"2026-09-29T00:00:00.000Z","score":0.00207,"percentile":null},{"date":"2026-09-30T00:00:00.000Z","score":0.00207,"percentile":null},{"date":"2026-10-01T00:00:00.000Z","score":0.00207,"percentile":null},{"date":"2026-10-02T00:00:00.000Z","score":0.00207,"percentile":null},{"date":"2026-10-03T00:00:00.000Z","score":0.00207,"percentile":null},{"date":"2026-10-04T00:00:00.000Z","score":0.00207,"percentile":null},{"date":"2026-10-05T00:00:00.000Z","score":0.00207,"percentile":null},{"date":"2026-10-06T00:00:00.000Z","score":0.00207,"percentile":null},{"date":"2026-10-07T00:00:00.000Z","score":0.00207,"percentile":null},{"date":"2026-10-08T00:00:00.000Z","score":0.00207,"percentile":null},{"date":"2026-10-09T00:00:00.000Z","score":0.00207,"percentile":null},{"date":"2026-10-10T00:00:00.000Z","score":0.00207,"percentile":null},{"date":"2026-10-11T00:00:00.000Z","score":0.00207,"percentile":null},{"date":"2026-10-12T00:00:00.000Z","score":0.00207,"percentile":null},{"date":"2026-10-13T00:00:00.000Z","score":0.00207,"percentile":null},{"date":"2026-10-14T00:00:00.000Z","score":0.00207,"percentile":null},{"date":"2026-10-15T00:00:00.000Z","score":0.00207,"percentile":null},{"date":"2026-10-16T00:00:00.000Z","score":0.00207,"percentile":null},{"date":"2026-10-17T00:00:00.000Z","score":0.00207,"percentile":null},{"date":"2026-10-18T00:00:00.000Z","score":0.00207,"percentile":null},{"date":"2026-10-19T00:00:00.000Z","score":0.00207,"percentile":null},{"date":"2026-10-20T00:00:00.000Z","score":0.00207,"percentile":0.1021}],"last30":[{"date":"2026-09-20T00:00:00.000Z","score":0.00196,"percentile":null},{"date":"2026-09-21T00:00:00.000Z","score":0.00196,"percentile":null},{"date":"2026-09-22T00:00:00.000Z","score":0.00196,"percentile":null},{"date":"2026-09-23T00:00:00.000Z","score":0.00196,"percentile":null},{"date":"2026-09-24T00:00:00.000Z","score":0.00207,"percentile":null},{"date":"2026-09-25T00:00:00.000Z","score":0.00207,"percentile":null},{"date":"2026-09-26T00:00:00.000Z","score":0.00207,"percentile":null},{"date":"2026-09-27T00:00:00.000Z","score":0.00207,"percentile":null},{"date":"2026-09-28T00:00:00.000Z","score":0.00207,"percentile":null},{"date":"2026-09-29T00:00:00.000Z","score":0.00207,"percentile":null},{"date":"2026-09-30T00:00:00.000Z","score":0.00207,"percentile":null},{"date":"2026-10-01T00:00:00.000Z","score":0.00207,"percentile":null},{"date":"2026-10-02T00:00:00.000Z","score":0.00207,"percentile":null},{"date":"2026-10-03T00:00:00.000Z","score":0.00207,"percentile":null},{"date":"2026-10-04T00:00:00.000Z","score":0.00207,"percentile":null},{"date":"2026-10-05T00:00:00.000Z","score":0.00207,"percentile":null},{"date":"2026-10-06T00:00:00.000Z","score":0.00207,"percentile":null},{"date":"2026-10-07T00:00:00.000Z","score":0.00207,"percentile":null},{"date":"2026-10-08T00:00:00.000Z","score":0.00207,"percentile":null},{"date":"2026-10-09T00:00:00.000Z","score":0.00207,"percentile":null},{"date":"2026-10-10T00:00:00.000Z","score":0.00207,"percentile":null},{"date":"2026-10-11T00:00:00.000Z","score":0.00207,"percentile":null},{"date":"2026-10-12T00:00:00.000Z","score":0.00207,"percentile":null},{"date":"2026-10-13T00:00:00.000Z","score":0.00207,"percentile":null},{"date":"2026-10-14T00:00:00.000Z","score":0.00207,"percentile":null},{"date":"2026-10-15T00:00:00.000Z","score":0.00207,"percentile":null},{"date":"2026-10-16T00:00:00.000Z","score":0.00207,"percentile":null},{"date":"2026-10-17T00:00:00.000Z","score":0.00207,"percentile":null},{"date":"2026-10-18T00:00:00.000Z","score":0.00207,"percentile":null},{"date":"2026-10-19T00:00:00.000Z","score":0.00207,"percentile":null},{"date":"2026-10-20T00:00:00.000Z","score":0.00207,"percentile":0.1021}]},"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":"arista networks","product":"eos","name":"EOS","label":"eos","ecosystem":null,"cpePart":"a","purl":null,"purlType":null,"versions":[{"text":"≥ 4.36.0, ≤ 4.36.1F","noFixRecorded":false,"fixedIn":null},{"text":"≥ 4.35.0, ≤ 4.35.5M","noFixRecorded":false,"fixedIn":null},{"text":"≥ 4.34.0, ≤ 4.34.7.1M","noFixRecorded":false,"fixedIn":null},{"text":"≥ 4.33.0, ≤ 4.33.9M","noFixRecorded":false,"fixedIn":null}],"versionsText":"≥ 4.36.0, ≤ 4.36.1F | ≥ 4.35.0, ≤ 4.35.5M | ≥ 4.34.0, ≤ 4.34.7.1M | ≥ 4.33.0, ≤ 4.33.9M","eol":null,"hubHref":"/vendor/arista_networks/eos"}],"affectedCount":1,"eol":{"hasEol":false,"count":0},"references":[{"url":"https://www.arista.com/en/support/advisories-notices/security-advisory/24712-security-advisory-0156","label":"www.arista.com/en/support/advisories-notices/security-advisory/24712-security-advisory-0156","hostname":"www.arista.com","tags":["Vendor Advisory"]}],"lineage":{"upstream":[],"downstream":[],"duplicates":[],"related":[]},"timeline":[{"kind":"published","date":"2026-09-15T21:02:49.314Z","label":"Published","detail":"Vulnerability first disclosed.","source":null},{"kind":"modified","date":"2026-09-17T03:57:04.541Z","label":"Last modified","detail":"Vulnerability information updated.","source":null}],"risk":{"score":70,"level":"high","profile":"Default","thresholds":{"critical":75,"high":50,"medium":25,"low":10}},"meta":{"dataAsOf":"2026-10-20T18:51:37.042Z","stale":false,"partial":false}}