CVE-2025-20111: Cisco NX-OS Software

High severity, CVSS 7.4. EPSS: 0.3% chance of exploitation in the next 30 days.

A vulnerability in the health monitoring diagnostics of Cisco Nexus 3000 Series Switches and Cisco Nexus 9000 Series Switches in standalone NX-OS mode could allow an unauthenticated, adjacent attacker to cause the device to reload unexpectedly, resulting in a denial of service (DoS) condition. This vulnerability is due to the incorrect handling of specific Ethernet frames. An attacker could exploit this vulnerability by sending a sustained rate of crafted Ethernet frames to an affected device. A successful exploit could allow the attacker to cause the device to reload.

Affected products

• Cisco Cisco NX-OS Software: version 9.3(2) only; version 9.3(1) only; version 9.3(1z) only; version 9.3(3) only; version 9.3(4) only; version 9.3(5) only; …

Published 2025-02-26. Last modified 2026-06-17.