# CVE-2026-73450

## Summary

- **CVE ID:** CVE-2026-73450
- **Severity:** HIGH
- **CVSS Score:** 7 (CVSS:4.0/AV:A/AC:L/AT:P/PR:N/UI:N/VC:N/VI:L/VA:H/SC:N/SI:N/SA:H)
- **CWE:** CWE-345
- **Published:** Sep 16, 2026
- **Last Modified:** Sep 17, 2026

## Description

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.

## Affected Products

- Arista Networks — EOS (4.36.0)
- Arista Networks — EOS (4.35.0)
- Arista Networks — EOS (4.34.0)
- Arista Networks — EOS (4.33.0)
- Arista Networks — EOS (0.0.0)

## References

- [CNA](https://www.arista.com/en/support/advisories-notices/security-advisory/24717-security-advisory-0161)

## Exploitation Prediction (EPSS)

- **EPSS Score:** 0.13%
- **EPSS Percentile:** 3.1

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_Exported from OnDuty AI Vulnerability Intelligence on 2026-09-17._