Description
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 An authenticated user whose access was revoked by the new policy may retain unauthorized access to gRPC interfaces.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.
Affected products
| Vendor | Product | Affected | Fixed |
|---|---|---|---|
| Arista Networks | EOS | 4.36.0F – ≤ 4.36.0.1F, 4.35.0F – ≤ 4.35.5M, 4.34.0F – ≤ 4.34.7M, 4.33.0F – ≤ 4.33.8M, 4.32.0F – ≤ 4.32.11M, 4.31.0F – ≤ 4.31.10M | — |
Advisories 1
- WID-SEC-2026-3441 Arista EOS: Mehrere Schwachstellen BSI CERT-Bund (WID) · Sep 16, 2026
References
- Security Advisory 0169 vendor-advisory