Vulnerability in Arista Networks Eos

CVE-2026-73450

On affected platforms running Arista EOS with MLAG Dual Primary Detection configured, an unauthenticated attacker with access to the Dual Primary Detection network segment can send specially crafted packets to interfere with the dual-primary state. If the MLAG primary switch fails while these packets are present, the secondary switch incorrectly concludes it is in a dual-primary condition and err-disables its interfaces, leading to a traffic interruption.

CVSS v3 metric

CVSS v3 base score 6.9 (Medium). Vector: CVSS:3.1/AV:A/AC:H/PR:N/UI:N/S:C/C:N/I:L/A:H.

Affected products

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2026-73450?
CVE-2026-73450 is a medium-severity vulnerability in Arista Networks Eos, classified under Insufficient Verification of Data Authenticity. CVSS score: 6.9/10. Published 2026-09-16.
How severe is CVE-2026-73450?
Medium severity. CVSS v3 base score is 6.9 out of 10.