CVE-2026-19655

On affected platforms running Arista EOS with Dynamic Host Configuration Protocol (DHCP) relay/snooping configured with the information option (Option 82), or with the DHCP server configured with match criteria based on the information option, an unauthenticated attacker connected to a client-facing VLAN(s) where the relay is configured can send a specially crafted packet that causes the DHCP Relay service to restart.

CVSS v3 6.5 MEDIUM

6.5^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 2.8 / Impact : 3.6

Attack Vector ADJACENT_NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact NONE

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://www.arista.com/en/support/advisories-notices/security-advisory/24711-security-advisory-0155

Configurations

No configuration.

History

No history.

Information

Published : 2026-09-15 21:16

Updated : 2026-09-15 21:16

NVD link : CVE-2026-19655

Mitre link : CVE-2026-19655

CVE.ORG link : CVE-2026-19655

JSON object : View

Products Affected

No product.

CWE

CWE-20

Improper Input Validation

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