CVE-2026-73437 — CRITICAL (9.6)

Vulnerability Description

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 Score

9.6

CRITICAL

CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H

Attack Vector

ADJACENT_NETWORK

Attack Complexity

LOW

Privileges Required

NONE

User Interaction

NONE

Scope

CHANGED

Confidentiality

HIGH

Integrity

HIGH

Availability

HIGH

Related Weaknesses (CWE)

CWE-345

References

https://www.arista.com/en/support/advisories-notices/security-advisory/24712-sec

FAQ

What is CVE-2026-73437?

CVE-2026-73437 is a vulnerability with a CVSS score of 9.6 (CRITICAL). 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 a...

How severe is CVE-2026-73437?

CVE-2026-73437 has been rated CRITICAL with a CVSS base score of 9.6/10. This is considered a critical vulnerability requiring immediate attention.

Is there a patch for CVE-2026-73437?

Check the references section above for vendor advisories and patch information. Review vendor security bulletins for remediation guidance.