CVE-2026-121370

{"dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": {"cveId": "CVE-2026-121370", "assignerOrgId": "c8b34d1a-69ae-45c3-88fe-f3b3d44f39b7", "state": "PUBLISHED", "assignerShortName": "Arista", "dateReserved": "2026-11-03T11:27:14.150Z", "datePublished": "2026-11-10T20:10:01.435Z", "dateUpdated": "2026-11-10T22:02:12.078Z"}, "containers": {"cna": {"providerMetadata": {"orgId": "c8b34d1a-69ae-45c3-88fe-f3b3d44f39b7", "shortName": "Arista", "dateUpdated": "2026-11-10T20:10:01.435Z"}, "title": "Security Advisory 0224", "descriptions": [{"lang": "en", "value": "On affected platforms running Arista EOS with Precision Time Protocol (PTP) configured, an unauthenticated attacker with network access to a PTP-enabled port can create a denial of service (DoS) condition by sending traffic to the system."}], "affected": [{"vendor": "Arista Networks", "product": "EOS", "defaultStatus": "unaffected", "versions": [{"version": "4.34.0F", "status": "affected", "versionType": "custom", "lessThanOrEqual": "4.34.1F"}, {"version": "4.33.0F", "status": "affected", "versionType": "custom", "lessThanOrEqual": "4.33.8M"}, {"version": "4.32.0F", "status": "affected", "versionType": "custom", "lessThan": "4.33.0F"}, {"version": "4.31.0F", "status": "affected", "versionType": "custom", "lessThan": "4.32.0F"}, {"version": "4.30.0F", "status": "affected", "versionType": "custom", "lessThan": "4.31.0F"}, {"version": "4.29.2F", "status": "affected", "versionType": "custom", "lessThan": "4.30.0F"}], "platforms": ["750X Series"]}], "metrics": [{"cvssV3_1": {"version": "3.1", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:H", "baseScore": 8.6, "baseSeverity": "HIGH"}}, {"cvssV4_0": {"version": "4.0", "vectorString": "CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:H", "baseScore": 9.2, "baseSeverity": "CRITICAL"}}], "references": [{"url": "https://www.arista.com/en/support/advisories-notices/security-advisory/25046-security-advisory-0224", "tags": ["vendor-advisory"]}], "source": {"defects": ["1860051"], "advisory": "Security Advisory 0224", "discovery": "INTERNAL"}, "problemTypes": [{"descriptions": [{"lang": "en", "type": "CWE", "cweId": "CWE-770", "description": "CWE-770 Allocation of Resources Without Limits or Throttling"}]}], "configurations": [{"lang": "en", "value": "switch>show ptp\nPTP Mode: Boundary Clock\nPTP Profile: Default ( IEEE1588 )\nClock Identity: XX:XX:XX:XX:XX:XX:XX:XX\nGrandmaster Clock Identity: XX:XX:XX:XX:XX:XX:XX:XX\nNumber of slave ports: 0\nNumber of master ports: 1\nOffset From Master (nanoseconds): 0\nMean Path Delay (nanoseconds): 0\nSteps Removed: 0\nSkew (estimated local-to-master clock frequency ratio): 1.0\n Interface State Transport Delay \n Mechanism\n--------------- ------------ --------------- ---------\n Et1 Master ipv4 e2e", "supportingMedia": [{"base64": false, "type": "text/html", "value": "<pre>switch>show ptp\nPTP Mode: Boundary Clock\nPTP Profile: Default ( IEEE1588 )\nClock Identity: XX:XX:XX:XX:XX:XX:XX:XX\nGrandmaster Clock Identity: XX:XX:XX:XX:XX:XX:XX:XX\nNumber of slave ports: 0\nNumber of master ports: 1\nOffset From Master (nanoseconds): 0\nMean Path Delay (nanoseconds): 0\nSteps Removed: 0\nSkew (estimated local-to-master clock frequency ratio): 1.0\n Interface State Transport Delay \n Mechanism\n--------------- ------------ --------------- ---------\n Et1 Master ipv4 e2e</pre>"}]}], "workarounds": [{"lang": "en", "value": "switch# platform trident Linecard* diag mod MMU_MAX_BUCKET_QLAYER 1 1 THD_SEL=0x4d REFRESH=0x28\nswitch# platform trident Linecard* diag mod MMU_MIN_BUCKET_QLAYER 1 1 THD_SEL=0x10 REFRESH=0x8\n\nNote: If PTP is currently enabled on any interfaces, disable it on those interfaces before running the mitigation commands, then re-enable it afterward.\n\nTo disable PTP on an interface:\nswitch(config-if)# no ptp enable\n\nNote: These settings are not persistent. They must be re-applied after any forwarding plane reset or line card replacement.", "supportingMedia": [{"base64": false, "type": "text/html", "value": "<pre>switch# platform trident Linecard* diag mod MMU_MAX_BUCKET_QLAYER 1 1 THD_SEL=0x4d REFRESH=0x28\nswitch# platform trident Linecard* diag mod MMU_MIN_BUCKET_QLAYER 1 1 THD_SEL=0x10 REFRESH=0x8\n\nNote: If PTP is currently enabled on any interfaces, disable it on those interfaces before running the mitigation commands, then re-enable it afterward.\n\nTo disable PTP on an interface:\nswitch(config-if)# no ptp enable\n\nNote: These settings are not persistent. They must be re-applied after any forwarding plane reset or line card replacement.</pre>"}]}], "impacts": [{"capecId": "CAPEC-130", "descriptions": [{"lang": "en", "value": "CAPEC-130 Excessive Allocation"}]}]}, "adp": [{"metrics": [{"other": {"type": "ssvc", "content": {"id": "CVE-2026-121370", "role": "CISA Coordinator", "options": [{"Exploitation": "none"}, {"Automatable": "yes"}, {"Technical Impact": "partial"}], "version": "2.0.3", "timestamp": "2026-11-10T21:23:15.251420Z"}}}], "title": "CISA ADP Vulnrichment", "providerMetadata": {"orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "shortName": "CISA-ADP", "dateUpdated": "2026-11-10T22:02:12.078Z"}}]}}

{"dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": {"cveId": "CVE-2026-121370", "assignerOrgId": "c8b34d1a-69ae-45c3-88fe-f3b3d44f39b7", "state": "PUBLISHED", "assignerShortName": "Arista", "dateReserved": "2026-11-03T11:27:14.150Z", "datePublished": "2026-11-10T20:10:01.435Z", "dateUpdated": "2026-11-10T22:02:12.078Z"}, "containers": {"cna": {"providerMetadata": {"orgId": "c8b34d1a-69ae-45c3-88fe-f3b3d44f39b7", "shortName": "Arista", "dateUpdated": "2026-11-10T20:10:01.435Z"}, "title": "Security Advisory 0224", "descriptions": [{"lang": "en", "value": "On affected platforms running Arista EOS with Precision Time Protocol (PTP) configured, an unauthenticated attacker with network access to a PTP-enabled port can create a denial of service (DoS) condition by sending traffic to the system."}], "affected": [{"vendor": "Arista Networks", "product": "EOS", "defaultStatus": "unaffected", "versions": [{"version": "4.34.0F", "status": "affected", "versionType": "custom", "lessThanOrEqual": "4.34.1F"}, {"version": "4.33.0F", "status": "affected", "versionType": "custom", "lessThanOrEqual": "4.33.8M"}, {"version": "4.32.0F", "status": "affected", "versionType": "custom", "lessThan": "4.33.0F"}, {"version": "4.31.0F", "status": "affected", "versionType": "custom", "lessThan": "4.32.0F"}, {"version": "4.30.0F", "status": "affected", "versionType": "custom", "lessThan": "4.31.0F"}, {"version": "4.29.2F", "status": "affected", "versionType": "custom", "lessThan": "4.30.0F"}], "platforms": ["750X Series"]}], "metrics": [{"cvssV3_1": {"version": "3.1", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:H", "baseScore": 8.6, "baseSeverity": "HIGH"}}, {"cvssV4_0": {"version": "4.0", "vectorString": "CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:H", "baseScore": 9.2, "baseSeverity": "CRITICAL"}}], "references": [{"url": "https://www.arista.com/en/support/advisories-notices/security-advisory/25046-security-advisory-0224", "tags": ["vendor-advisory"]}], "source": {"defects": ["1860051"], "advisory": "Security Advisory 0224", "discovery": "INTERNAL"}, "problemTypes": [{"descriptions": [{"lang": "en", "type": "CWE", "cweId": "CWE-770", "description": "CWE-770 Allocation of Resources Without Limits or Throttling"}]}], "configurations": [{"lang": "en", "value": "switch>show ptp\nPTP Mode: Boundary Clock\nPTP Profile: Default ( IEEE1588 )\nClock Identity: XX:XX:XX:XX:XX:XX:XX:XX\nGrandmaster Clock Identity: XX:XX:XX:XX:XX:XX:XX:XX\nNumber of slave ports: 0\nNumber of master ports: 1\nOffset From Master (nanoseconds): 0\nMean Path Delay (nanoseconds): 0\nSteps Removed: 0\nSkew (estimated local-to-master clock frequency ratio): 1.0\n Interface State Transport Delay \n Mechanism\n--------------- ------------ --------------- ---------\n Et1 Master ipv4 e2e", "supportingMedia": [{"base64": false, "type": "text/html", "value": "<pre>switch>show ptp\nPTP Mode: Boundary Clock\nPTP Profile: Default ( IEEE1588 )\nClock Identity: XX:XX:XX:XX:XX:XX:XX:XX\nGrandmaster Clock Identity: XX:XX:XX:XX:XX:XX:XX:XX\nNumber of slave ports: 0\nNumber of master ports: 1\nOffset From Master (nanoseconds): 0\nMean Path Delay (nanoseconds): 0\nSteps Removed: 0\nSkew (estimated local-to-master clock frequency ratio): 1.0\n Interface State Transport Delay \n Mechanism\n--------------- ------------ --------------- ---------\n Et1 Master ipv4 e2e</pre>"}]}], "workarounds": [{"lang": "en", "value": "switch# platform trident Linecard* diag mod MMU_MAX_BUCKET_QLAYER 1 1 THD_SEL=0x4d REFRESH=0x28\nswitch# platform trident Linecard* diag mod MMU_MIN_BUCKET_QLAYER 1 1 THD_SEL=0x10 REFRESH=0x8\n\nNote: If PTP is currently enabled on any interfaces, disable it on those interfaces before running the mitigation commands, then re-enable it afterward.\n\nTo disable PTP on an interface:\nswitch(config-if)# no ptp enable\n\nNote: These settings are not persistent. They must be re-applied after any forwarding plane reset or line card replacement.", "supportingMedia": [{"base64": false, "type": "text/html", "value": "<pre>switch# platform trident Linecard* diag mod MMU_MAX_BUCKET_QLAYER 1 1 THD_SEL=0x4d REFRESH=0x28\nswitch# platform trident Linecard* diag mod MMU_MIN_BUCKET_QLAYER 1 1 THD_SEL=0x10 REFRESH=0x8\n\nNote: If PTP is currently enabled on any interfaces, disable it on those interfaces before running the mitigation commands, then re-enable it afterward.\n\nTo disable PTP on an interface:\nswitch(config-if)# no ptp enable\n\nNote: These settings are not persistent. They must be re-applied after any forwarding plane reset or line card replacement.</pre>"}]}], "impacts": [{"capecId": "CAPEC-130", "descriptions": [{"lang": "en", "value": "CAPEC-130 Excessive Allocation"}]}]}, "adp": [{"title": "CISA ADP Vulnrichment", "metrics": [{"other": {"type": "ssvc", "content": {"id": "CVE-2026-121370", "role": "CISA Coordinator", "options": [{"Exploitation": "none"}, {"Automatable": "yes"}, {"Technical Impact": "partial"}], "version": "2.0.3", "timestamp": "2026-11-10T21:23:15.251420Z"}}}], "providerMetadata": {"orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "shortName": "CISA-ADP", "dateUpdated": "2026-11-10T21:58:38.415Z"}}]}}

{"affected": [{"affectedData": [{"defaultStatus": "unaffected", "platforms": ["750X Series"], "product": "EOS", "vendor": "Arista Networks", "versions": [{"lessThanOrEqual": "4.34.1F", "status": "affected", "version": "4.34.0F", "versionType": "custom"}, {"lessThanOrEqual": "4.33.8M", "status": "affected", "version": "4.33.0F", "versionType": "custom"}, {"lessThan": "4.33.0F", "status": "affected", "version": "4.32.0F", "versionType": "custom"}, {"lessThan": "4.32.0F", "status": "affected", "version": "4.31.0F", "versionType": "custom"}, {"lessThan": "4.31.0F", "status": "affected", "version": "4.30.0F", "versionType": "custom"}, {"lessThan": "4.30.0F", "status": "affected", "version": "4.29.2F", "versionType": "custom"}]}], "source": "psirt@arista.com"}], "cveTags": [], "descriptions": [{"lang": "en", "value": "On affected platforms running Arista EOS with Precision Time Protocol (PTP) configured, an unauthenticated attacker with network access to a PTP-enabled port can create a denial of service (DoS) condition by sending traffic to the system."}], "id": "CVE-2026-121370", "lastModified": "2026-11-12T19:24:37.847", "metrics": {"cvssMetricV31": [{"cvssData": {"attackComplexity": "LOW", "attackVector": "NETWORK", "availabilityImpact": "HIGH", "baseScore": 8.6, "baseSeverity": "HIGH", "confidentialityImpact": "NONE", "integrityImpact": "NONE", "privilegesRequired": "NONE", "scope": "CHANGED", "userInteraction": "NONE", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:H", "version": "3.1"}, "exploitabilityScore": 3.9, "impactScore": 4.0, "source": "psirt@arista.com", "type": "Secondary"}], "cvssMetricV40": [{"cvssData": {"Automatable": "NOT_DEFINED", "Recovery": "NOT_DEFINED", "Safety": "NOT_DEFINED", "attackComplexity": "LOW", "attackRequirements": "NONE", "attackVector": "NETWORK", "availabilityRequirement": "NOT_DEFINED", "baseScore": 9.2, "baseSeverity": "CRITICAL", "confidentialityRequirement": "NOT_DEFINED", "exploitMaturity": "NOT_DEFINED", "integrityRequirement": "NOT_DEFINED", "modifiedAttackComplexity": "NOT_DEFINED", "modifiedAttackRequirements": "NOT_DEFINED", "modifiedAttackVector": "NOT_DEFINED", "modifiedPrivilegesRequired": "NOT_DEFINED", "modifiedSubAvailabilityImpact": "NOT_DEFINED", "modifiedSubConfidentialityImpact": "NOT_DEFINED", "modifiedSubIntegrityImpact": "NOT_DEFINED", "modifiedUserInteraction": "NOT_DEFINED", "modifiedVulnAvailabilityImpact": "NOT_DEFINED", "modifiedVulnConfidentialityImpact": "NOT_DEFINED", "modifiedVulnIntegrityImpact": "NOT_DEFINED", "privilegesRequired": "NONE", "providerUrgency": "NOT_DEFINED", "subAvailabilityImpact": "HIGH", "subConfidentialityImpact": "NONE", "subIntegrityImpact": "NONE", "userInteraction": "NONE", "valueDensity": "NOT_DEFINED", "vectorString": "CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/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", "version": "4.0", "vulnAvailabilityImpact": "HIGH", "vulnConfidentialityImpact": "NONE", "vulnIntegrityImpact": "NONE", "vulnerabilityResponseEffort": "NOT_DEFINED"}, "source": "psirt@arista.com", "type": "Secondary"}], "ssvcV203": [{"source": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "ssvcData": {"id": "CVE-2026-121370", "options": [{"exploitation": "none"}, {"automatable": "yes"}, {"technicalImpact": "partial"}], "role": "CISA Coordinator", "timestamp": "2026-11-10T21:23:15.251420Z", "version": "2.0.3"}}]}, "published": "2026-11-10T20:18:56.507", "references": [{"source": "psirt@arista.com", "url": "https://www.arista.com/en/support/advisories-notices/security-advisory/25046-security-advisory-0224"}], "sourceIdentifier": "psirt@arista.com", "vulnStatus": "Awaiting Analysis", "weaknesses": [{"description": [{"lang": "en", "value": "CWE-770"}], "source": "psirt@arista.com", "type": "Secondary"}]}

{}

{"affected": [{"configurations": [{"platform": ["750x_series"], "status": "affected", "versions": {"scheme": "generic", "value": "[4.34.0F,4.34.1F]"}}, {"platform": ["750x_series"], "status": "affected", "versions": {"scheme": "generic", "value": "[4.33.0F,4.33.8M]"}}, {"platform": ["750x_series"], "status": "affected", "versions": {"scheme": "generic", "value": "[4.32.0F,4.33.0F)"}}, {"platform": ["750x_series"], "status": "affected", "versions": {"scheme": "generic", "value": "[4.31.0F,4.32.0F)"}}, {"platform": ["750x_series"], "status": "affected", "versions": {"scheme": "generic", "value": "[4.30.0F,4.31.0F)"}}, {"platform": ["750x_series"], "status": "affected", "versions": {"scheme": "generic", "value": "[4.29.2F,4.30.0F)"}}], "enrichment": {"confidence": 100.0, "confidence_source": "matching", "scores": [{"score": 100.0, "source": "matching"}]}, "original": {"product": "EOS", "source": "cna", "vendor": "Arista Networks"}, "product": "eos", "vendor": "arista"}], "created": "2026-11-11T22:30:18.304359+00:00", "title": "Denial of Service via Unauthenticated PTP Traffic in Arista EOS", "updated": "2026-11-13T10:15:19.236091+00:00", "vendors": ["arista", "arista$PRODUCT$eos"]}