CVE-2026-73451 Security feature bypass in EOS
Restarting secondary switchcards on Arista EOS devices with specific ACL configurations can disable security filters, allowing unauthorized network traffic.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- None listed
What is CVE-2026-73451?
CVE-2026-73451 is a medium-severity vulnerability in Arista Networks EOS, published on 15 Sep 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.
Official description
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.
Weakness: CWE-1419
Which versions are affected by CVE-2026-73451?
How do I fix CVE-2026-73451?
No fix has been published for CVE-2026-73451 yet. Limit exposure of the affected software until one is available.
Is CVE-2026-73451 being exploited?
There is no known exploitation of CVE-2026-73451 in the wild and no public exploit code.
Sources
Also known as GHSA-66c7-m7g9-9qrj.