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arista-networksCVE-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...

Medium6.5CVE-2026-73437 · Published Sep 15, 2026 · updated Sep 17, 2026

Source advisory

Affected versions

PackageAffectedFixed in
EOS
Vendor
>= 4.36.0, <= 4.36.1FNo fix yet
>= 4.35.0, <= 4.35.5MNo fix yet
>= 4.34.0, <= 4.34.7.1MNo fix yet
>= 4.33.0, <= 4.33.9MNo fix yet
Details and references

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 4.0
CVSS:4.0/AV:A/AC:L/AT:N/PR:N/UI:N/VC:N/VI:L/VA:N/SC:H/SI:H/SA:H/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
Severity from
no source yet
Weakness
CWE-345

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