CVE-2026-73451: Arista Networks Eos

Medium severity, CVSS 4.8. EPSS: 0.2% chance of exploitation in the next 30 days.

On affected platforms running Arista EOS with dual switch cards and with ingress Security ACLs configured on Switched Virtual Interfaces (SVI) in shared mode, restarting of the secondary switchcard forwarding agent or insertion of secondary switchcard, can cause security ACLs on shared SVIs to stop functioning. This may result in incorrect packet permit/deny behavior. 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

• Arista Networks Eos: from 4.36.0, up to and including 4.36.0.1F; from 4.35.0, up to and including 4.35.4M; from 4.34.0, up to and including 4.34.6M; from 4.33.0, up to and including 4.33.8M; from 4.32.0, up to and including 4.32.11M; from 4.31.1F, up to and including 4.31.10M

Published 2026-09-15. Last modified 2026-09-16.