CVE-2026-73456

Summary

Under certain circumstances on affected platforms running Arista EOS with gRPC Network Packet Sampling Interface (gNPSI) enabled, an unauthenticated gNPSI client can craft a malicious request to allow arbitrary code execution, granting an attacker full administrative control over the compromised switch.

Affected Software

VendorProductVersion RangeStatus
Arista NetworksEOS4.36.0 <= 4.36.1Faffected
Arista NetworksEOS4.35.0 <= 4.35.5Maffected
Arista NetworksEOS4.34.2F <= 4.34.7Maffected

Weaknesses

  • CWE-94: CWE-94 Improper Control of Generation of Code ('Code Injection')

Workarounds

To secure the agent against CVE-2026-73456, configure the service to use mutual TLS and enable only x509-spiffe authentication:

management security ssl profile P1 certificate server.crt key server.key trust certificate ca_client.crt chain certificate ca_signing.crt ! management api gnpsi transport grpc t2 ssl profile P1 port 7001 authentication username priority x509-spiffe no disabled

References