CVE-2026-121367: Security Advisory 0220

On affected Arista EOS platforms with Routing Information Protocol version 2 (RIPv2) configured, under certain conditions, RIPv2 might be silently enabled on management interfaces even when the RIP agent intends to disable it. It allows an unauthenticated attacker with access to the adjacent network to send crafted RIPv2 route advertisements to the device's management IP address. The device could accept and install those routes without authentication.

Successful exploitation could allow the attacker to redirect traffic flows to an attacker-controlled destination, install more-specific routes that blackhole legitimate traffic, or otherwise disrupt network reachability for systems whose traffic passes through the affected device.