CVE-2026-73453

Critical

Description

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.

SeverityCritical
CVSS10.0
Exploit probability—
ProductEOS
PublishedSep 16, 2026
First seenSep 16, 2026

How to fix

Update
  • Arista Networks EOS4.34.0F, 4.33.0F, 4.32.0F, 4.31.0F, 4.30.0F or later

Affected products

ProductAffected versionsFixed in
Arista Networks EOS4.36.0F ≤ v ≤ 4.36.1F, 4.35.0F ≤ v ≤ 4.35.5M, 4.34.0F ≤ v ≤ 4.34.7M, 4.33.0F ≤ v < 4.34.0F, 4.32.0F ≤ v < 4.33.0F, 4.31.0F ≤ v < 4.32.0F, 4.30.0F ≤ v < 4.31.0F, 4.29.2F ≤ v < 4.30.0F4.34.0F, 4.33.0F, 4.32.0F, 4.31.0F, 4.30.0F

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