CVE-2026-73437

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.

CVSS v3 9.6 CRITICAL

9.6^/10

CVSS v3 : CRITICAL

Vector :

Exploitability : 2.8 / Impact : 6.0

Attack Vector ADJACENT_NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact HIGH

Scope CHANGED

References

Link	Resource
https://www.arista.com/en/support/advisories-notices/security-advisory/24712-security-advisory-0156

Configurations

No configuration.

History

No history.

Information

Published : 2026-09-15 22:16

Updated : 2026-09-15 22:16

NVD link : CVE-2026-73437

Mitre link : CVE-2026-73437

CVE.ORG link : CVE-2026-73437

JSON object : View

Products Affected

No product.

CWE

CWE-345

Insufficient Verification of Data Authenticity

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