CVE-2026-73450

On affected platforms running Arista EOS with MLAG Dual Primary Detection configured, an unauthenticated attacker with access to the Dual Primary Detection network segment can send specially crafted packets to interfere with the dual-primary state. If the MLAG primary switch fails while these packets are present, the secondary switch incorrectly concludes it is in a dual-primary condition and err-disables its interfaces, leading to a traffic interruption.

CVSS v3 6.9 MEDIUM

6.9^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 1.6 / Impact : 4.7

Attack Vector ADJACENT_NETWORK

Attack Complexity HIGH

Privileges Required NONE

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact LOW

Availability Impact HIGH

Scope CHANGED

References

Link	Resource
https://www.arista.com/en/support/advisories-notices/security-advisory/24717-security-advisory-0161

Configurations

No configuration.

History

No history.

Information

Published : 2026-09-16 03:16

Updated : 2026-09-16 03:16

NVD link : CVE-2026-73450

Mitre link : CVE-2026-73450

CVE.ORG link : CVE-2026-73450

JSON object : View

Products Affected

No product.

CWE

CWE-345

Insufficient Verification of Data Authenticity

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