DHCP Relay Vulnerability in Arista EOS Products
CVE-2026-73437

6.5MEDIUM

Key Information:

Vendor

Arista Networks

Status
Eos
Vendor
CVE Published:
15 September 2026

What is CVE-2026-73437?

On platforms utilizing Arista EOS with DHCP relay enabled, an unauthenticated attacker on the network can send a crafted DHCP reply packet from an unauthorized IP address. The relay agent may forward this packet to clients without proper source validation, allowing the attacker to deliver malicious network configuration settings. This could lead to severe consequences such as traffic interception or denial of service for the impacted clients.

Affected Version(s)

EOS 710 Series 4.36.0 <= 4.36.1F

EOS 710 Series 4.35.0 <= 4.35.5M

EOS 710 Series 4.34.0 <= 4.34.7.1M

References

https://www.arista.com/en/support/advisories-notices/secu...
vendor-advisory

CVSS V4

Score:
6.5
Severity:
MEDIUM
Confidentiality:
None
Integrity:
Low
Availability:
None
Attack Vector:
Adjacent Network
Attack Complexity:
Low
Attack Required:
None
Privileges Required:
Undefined
User Interaction:
None

Timeline

  • Vulnerability published

  • Vulnerability Reserved

Credit

This issue was discovered internally by Arista.
.