CVE-2026-73463

On affected platforms running Arista EOS, when multiple gRPC Network Security Interface (gNSI) transports are configured, a race condition in the gNSI Authz service may cause a policy rotation to fail silently. An authenticated user whose access was revoked by the new policy may retain unauthorized access to gRPC interfaces. This does not affect Bootz. This issue was discovered internally by Arista, and the company is not aware of any malicious exploitation of this vulnerability in customer networks.

CVSS v3 5.3 MEDIUM

5.3^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 1.6 / Impact : 3.6

Attack Vector NETWORK

Attack Complexity HIGH

Privileges Required LOW

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact HIGH

Availability Impact NONE

Scope UNCHANGED

References

Link	Resource
https://www.arista.com/en/support/advisories-notices/security-advisory/24725-security-advisory-0169

Configurations

No configuration.

History

No history.

Information

Published : 2026-09-16 09:17

Updated : 2026-09-16 11:16

NVD link : CVE-2026-73463

Mitre link : CVE-2026-73463

CVE.ORG link : CVE-2026-73463

JSON object : View

Products Affected

No product.

CWE

CWE-362

Concurrent Execution using Shared Resource with Improper Synchronization ('Race Condition')

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