Critical · published September 16, 2026
An unauthenticated P4Runtime (Programming Protocol-Independent Packet Processors Runtime) client can achieve arbitrary code execution under certain conditions on affected platforms running Arista EOS configured with P4Runtime. P4Runtime is disabled by default in Arista EOS. By crafting a malicious packet during the initiation of a P4Runtime session, an attacker can obtain complete administrative control over the compromised switch.
This issue was discovered internally by Arista, and the company is not aware of any malicious exploitation of this vulnerability in customer networks.