CVE-2024-20371: Cisco Nexus 3550 System Software

Medium severity, CVSS 5.3. EPSS: 0.5% chance of exploitation in the next 30 days.

A vulnerability in the access control list (ACL) programming of Cisco Nexus 3550-F Switches could allow an unauthenticated, remote attacker to send traffic that should be blocked to the management interface of an affected device.  This vulnerability exists because ACL deny rules are not properly enforced at the time of device reboot. An attacker could exploit this vulnerability by attempting to send traffic to the management interface of an affected device. A successful exploit could allow the attacker to send traffic to the management interface of the affected device.

Affected products

• Cisco Cisco Nexus 3550 System Software: version 3550-F_1.11.3 only; version 3550-F_1.12.0 only; version 3550-F_1.16.0 only; version 3550-F_1.17.1 only; version 3550-F_1.11.1 only; version 3550-F_1.11.2 only; …
• Cisco Nexus 3550 Firmware: version 3550-F_1.11.3 only; version 3550-F_1.12.0 only; version 3550-F_1.16.0 only; version 3550-F_1.17.1 only; version 3550-F_1.11.1 only; version 3550-F_1.11.2 only; …

Published 2024-11-06. Last modified 2026-06-17.