CVE-2026-73443

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.

CVSS v3 4.7 MEDIUM

4.7^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 2.8 / Impact : 1.4

Attack Vector ADJACENT_NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact NONE

Availability Impact LOW

Scope CHANGED

References

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

Configurations

No configuration.

History

16 Sep 2026, 19:17

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-09-16 19:17

Updated : 2026-09-17 19:16

NVD link : CVE-2026-73443

Mitre link : CVE-2026-73443

CVE.ORG link : CVE-2026-73443

JSON object : View

Products Affected

No product.

CWE

CWE-294

Authentication Bypass by Capture-replay

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