CVE-2026-121295 - Vulnerability Details - OpenCVE

On affected platforms running Arista EOS configured as S-BFD peers, an unauthenticated attacker could send a crafted S-BFD PDU to an initiator device. This crafted PDU could cause the kernel on the initiator device to crash, resulting in an unexpected device reboot.

Attack Vector Network

Attack Complexity Low

Privileges Required None

Attack Requirements None

User Interaction None

Vulnerable System Confidentiality Impact None

Vulnerable System Integrity Impact None

Vulnerable System Availability Impact High

Subsequent System Confidentiality Impact None

Subsequent System Integrity Impact None

Subsequent System Availability Impact High

Attack Vector Network

Attack Complexity Low

Privileges Required None

Scope Changed

Confidentiality Impact None

Integrity Impact None

Availability Impact High

User Interaction None

No CVSS v3.0

No CVSS v2

This CVE is not in the KEV list.

No EPSS score available.

Key SSVC decision points have not yet been added.

No data.

No data.

No data.

No data.

Advisories

No advisories yet.

Fixes

Solution

No solution given by the vendor.

Workaround

No workaround given by the vendor.

References

Link	Providers
https://www.arista.com/en/support/advisories-notices/security-advisory/25045-security-advisory-0223

History

Tue, 10 Nov 2026 20:15:00 +0000

Type	Values Removed	Values Added
Description		On affected platforms running Arista EOS configured as S-BFD peers, an unauthenticated attacker could send a crafted S-BFD PDU to an initiator device. This crafted PDU could cause the kernel on the initiator device to crash, resulting in an unexpected device reboot.
Title		Security Advisory 0223
Weaknesses		CWE-1284
References		https://www.arista.com/en/support/advisories-notices/security-advisory/25045-security-advisory-0223
Metrics		cvssV3_1 `{'score': 8.6, 'vector': 'CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:H'}` cvssV4_0 `{'score': 9.2, 'vector': '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'}`

Projects

Sign in to view the affected projects.

MITRE

Status: PUBLISHED

Assigner: Arista

Published: 2026-11-10T20:09:59.572Z

Updated: 2026-11-10T20:09:59.572Z

Reserved: 2026-11-03T11:21:01.892Z

Link: CVE-2026-121295

Vulnrichment

No data.

NVD

Status : Received

Published: 2026-11-10T20:18:55.750

Modified: 2026-11-10T20:18:55.750

Link: CVE-2026-121295

Redhat

No data.

OpenCVE Enrichment

No data.

Weaknesses

CWE-1284

{"dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": {"cveId": "CVE-2026-121295", "assignerOrgId": "c8b34d1a-69ae-45c3-88fe-f3b3d44f39b7", "state": "PUBLISHED", "assignerShortName": "Arista", "dateReserved": "2026-11-03T11:21:01.892Z", "datePublished": "2026-11-10T20:09:59.572Z", "dateUpdated": "2026-11-10T20:09:59.572Z"}, "containers": {"cna": {"providerMetadata": {"orgId": "c8b34d1a-69ae-45c3-88fe-f3b3d44f39b7", "shortName": "Arista", "dateUpdated": "2026-11-10T20:09:59.572Z"}, "title": "Security Advisory 0223", "descriptions": [{"lang": "en", "value": "On affected platforms running Arista EOS configured as S-BFD peers, an unauthenticated attacker could send a crafted S-BFD PDU to an initiator device. This crafted PDU could cause the kernel on the initiator device to crash, resulting in an unexpected device reboot."}], "affected": [{"vendor": "Arista Networks", "product": "EOS", "defaultStatus": "unaffected", "versions": [{"version": "4.36.0F", "status": "affected", "versionType": "custom", "lessThanOrEqual": "4.36.2F"}, {"version": "4.35.0F", "status": "affected", "versionType": "custom", "lessThanOrEqual": "4.35.6M"}, {"version": "4.34.0F", "status": "affected", "versionType": "custom", "lessThanOrEqual": "4.34.8M"}, {"version": "4.33.0F", "status": "affected", "versionType": "custom", "lessThanOrEqual": "4.33.10M"}, {"version": "4.32.0F", "status": "affected", "versionType": "custom", "lessThan": "4.33.0F"}, {"version": "1.0.0", "status": "affected", "versionType": "custom", "lessThan": "4.32.0F"}], "platforms": ["710 Series", "720D Series", "720XP/722XPM Series", "750X Series", "7010TX Series", "7020R/R4 Series", "7280R/R2/R3/R4 Series", "7500R/R2/R3 Series", "7800R3/R4 Series", "7700R4 Series", "CloudEOS", "cEOS-lab", "vEOS-lab", "CloudVision eXchange, virtual or physical appliance"]}], "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/25045-security-advisory-0223", "tags": ["vendor-advisory"]}], "source": {"defects": ["1966375"], "advisory": "Security Advisory 0223", "discovery": "INTERNAL"}, "problemTypes": [{"descriptions": [{"lang": "en", "type": "CWE", "cweId": "CWE-1284", "description": "CWE-1284 Improper Validation of Specified Quantity in Input"}]}], "configurations": [{"lang": "en", "value": "CVE-2026-121294:\nswitch#show running-config section sbfd\nrouter bfd\n sbfd\n reflector local-discriminator <DISC> proxy\n\nCVE-2026-121295:\nswitch#show running-config section sbfd\nrouter bfd\n sbfd\n initiator measurement delay round-trip", "supportingMedia": [{"base64": false, "type": "text/html", "value": "<pre>CVE-2026-121294:\nswitch#show running-config section sbfd\nrouter bfd\n sbfd\n reflector local-discriminator <DISC> proxy\n\nCVE-2026-121295:\nswitch#show running-config section sbfd\nrouter bfd\n sbfd\n initiator measurement delay round-trip</pre>"}]}], "impacts": [{"capecId": "CAPEC-100", "descriptions": [{"lang": "en", "value": "CAPEC-100 Overflow Buffers"}]}]}}}

{"affected": [{"affectedData": [{"defaultStatus": "unaffected", "platforms": ["710 Series", "720D Series", "720XP/722XPM Series", "750X Series", "7010TX Series", "7020R/R4 Series", "7280R/R2/R3/R4 Series", "7500R/R2/R3 Series", "7800R3/R4 Series", "7700R4 Series", "CloudEOS", "cEOS-lab", "vEOS-lab", "CloudVision eXchange, virtual or physical appliance"], "product": "EOS", "vendor": "Arista Networks", "versions": [{"lessThanOrEqual": "4.36.2F", "status": "affected", "version": "4.36.0F", "versionType": "custom"}, {"lessThanOrEqual": "4.35.6M", "status": "affected", "version": "4.35.0F", "versionType": "custom"}, {"lessThanOrEqual": "4.34.8M", "status": "affected", "version": "4.34.0F", "versionType": "custom"}, {"lessThanOrEqual": "4.33.10M", "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": "1.0.0", "versionType": "custom"}]}], "source": "[email protected]"}], "cveTags": [], "descriptions": [{"lang": "en", "value": "On affected platforms running Arista EOS configured as S-BFD peers, an unauthenticated attacker could send a crafted S-BFD PDU to an initiator device. This crafted PDU could cause the kernel on the initiator device to crash, resulting in an unexpected device reboot."}], "id": "CVE-2026-121295", "lastModified": "2026-11-10T20:18:55.750", "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": "[email protected]", "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": "[email protected]", "type": "Secondary"}]}, "published": "2026-11-10T20:18:55.750", "references": [{"source": "[email protected]", "url": "https://www.arista.com/en/support/advisories-notices/security-advisory/25045-security-advisory-0223"}], "sourceIdentifier": "[email protected]", "vulnStatus": "Received", "weaknesses": [{"description": [{"lang": "en", "value": "CWE-1284"}], "source": "[email protected]", "type": "Secondary"}]}