CVE-2026-73443

medium

Description

On affected platforms running Arista EOS with VRRPv2 IP-AH authentication configured, an unauthenticated attacker within the same layer 2 network segment on which VRRP is running can capture a legitimate authenticated VRRP advertisement and replay it indefinitely. Replayed advertisements can be used to advertise stale VRRP state, for example to prevent a backup router from taking over the virtual gateway after the original master has gone down, resulting in a denial of service for hosts using the virtual gateway address.

References

https://www.arista.com/en/support/advisories-notices/security-advisory/24713-security-advisory-0157

Details

Source: Mitre, NVD

Published: 2026-09-16

Updated: 2026-09-17

Risk Information

CVSS v2

Base Score: 3.3

Vector: CVSS2#AV:A/AC:L/Au:N/C:N/I:N/A:P

Severity: Low

CVSS v3

Base Score: 4.7

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

Severity: Medium

CVSS v4

Base Score: 5.3

Vector: CVSS:4.0/AV:A/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N