Critical 9.6Published Sep 15, 2026

CVE-2026-73437On 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/destinat

Updated under an hour ago (2026-10-19 07:10 UTC)

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It affects Arista Networks EOS. Add what you run to find out whether that includes you.

No exploitation reported and no EPSS estimate yet.

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Every CVE for Arista Networks EOS

Exploited in the last 30 days

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: 9.6 CRITICAL (v3.1, CNA)CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H
Weakness (CWE): CWE-345
Known exploited: Not in CISA's KEV catalog
EPSS (exploitation in the next 30 days): Not loaded for this CVE
Assigned by: Arista
NVD analysis: Awaiting Analysis
Record last updated: Sep 17, 2026
First seen by InfoSec Signals: Oct 9, 2026

Affected products

Affected products

Arista Networks EOS arista_networks:eos (from the name)	from 4.36.0 through 4.36.1F; fixed at 4.36.2F; from 4.35.0 through 4.35.5M; fixed at 4.35.6M; from 4.34.0 through 4.34.7.1M; fixed at 4.34.8M; from 4.33.0 through 4.33.9M; fixed at 4.33.10M	CNA record

References

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

The CVE record on cve.org NVD's entry

The CVE record is authoritative. Products marked “from the name” were identified from the CNA's free-text names, not a CPE, and are matched less certainly. This product uses the NVD API but is not endorsed or certified by the NVD.