Cisco NX-OS Software CLI Command Injection Vulnerability (CVE-2019-1609)

Vulnerability

CVE-2019-1609 is a command injection vulnerability in the CLI of Cisco NX-OS Software. The flaw is due to insufficient validation of arguments passed to certain CLI commands. Affected products include MDS 9000 Series Multilayer Switches (prior to versions 6.2(27), 8.1(1b), and 8.3(2)), Nexus 3500 Platform Switches (prior to 7.0(3)I7(6)), Nexus 3000 Series Switches (prior to 7.0(3)I4(9) and 7.0(3)I7(6)), Nexus 3600 Platform Switches (prior to 7.0(3)F3(5)), Nexus 7000 and 7700 Series Switches (prior to 6.2(22), 7.3(3)D1(1), 8.2(3), and 8.3(2)), Nexus 9000 Series Switches in Standalone NX-OS Mode (prior to 7.0(3)I4(9) and 7.0(3)I7(6)), and Nexus 9500 R-Series Line Cards and Fabric Modules (prior to 7.0(3)F3(5)). [1]

Exploitation

An attacker must have valid administrator credentials to exploit this vulnerability. The attacker would include malicious input as the argument of an affected CLI command. By authenticating locally and issuing the crafted command, the attacker triggers the injection. No user interaction beyond the attacker's own authenticated session is required. [1]

Impact

Successful exploitation allows the attacker to execute arbitrary commands on the underlying operating system of the device with elevated privileges. This can lead to full compromise of the affected switch, including complete loss of confidentiality, integrity, and availability. [1]

Mitigation

Cisco has released free software updates to address this vulnerability. Fixed versions are: MDS 9000 Series to 6.2(27) or later, 8.1(1b) or later, 8.3(2) or later; Nexus 3500 Platform to 7.0(3)I7(6) or later; Nexus 3000 Series to 7.0(3)I4(9) or later, 7.0(3)I7(6) or later; Nexus 3600 Platform to 7.0(3)F3(5) or later; Nexus 7000 and 7700 Series to 6.2(22) or later, 7.3(3)D1(1) or later, 8.2(3) or later, 8.3(2) or later; Nexus 9000 Series to 7.0(3)I4(9) or later, 7.0(3)I7(6) or later; Nexus 9500 R-Series Line Cards and Fabric Modules to 7.0(3)F3(5) or later. Customers should upgrade to a fixed release as described in the Cisco advisory. There is no workaround available. [1]