Cisco Nexus 9300-FX3 Series Fabric Extender for UCS Fabric Interconnects Authentication Bypass Vulnerability

A vulnerability in the CLI console login authentication of Cisco Nexus 9300-FX3 Series Fabric Extender (FEX) when used in UCS Fabric Interconnect deployments could allow an unauthenticated attacker with physical access to bypass authentication.

This vulnerability is due to the improper implementation of the password validation function. An attacker could exploit this vulnerability by logging in to the console port on an affected device. A successful exploit could allow the attacker to bypass authentication and execute a limited set of commands local to the FEX, which could cause a device reboot and denial of service (DoS) condition.

Cisco has released software updates that address this vulnerability. There are no workarounds that address this vulnerability.

This advisory is available at the following link:
https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-elyfex-dos-gfvcByx [“https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-elyfex-dos-gfvcByx”]

This advisory is part of the February 2023 Cisco FXOS and NX-OS Software Security Advisory Bundled Publication. For a complete list of the advisories and links to them, see Cisco Event Response: February 2023 Semiannual Cisco FXOS and NX-OS Software Security Advisory Bundled Publication [“https://sec.cloudapps.cisco.com/security/center/viewErp.x?alertId=ERP-75057”].