Cisco NX-OS User Account Management Interface improper authorization

Summaryinfo

A vulnerability described as critical has been identified in Cisco NX-OS. The affected element is an unknown function of the component User Account Management Interface. Executing a manipulation can lead to improper authorization. This vulnerability is registered as CVE-2019-1604. The attack needs to be launched locally. No exploit is available. Upgrading the affected component is recommended.

Detailsinfo

A vulnerability classified as critical was found in Cisco NX-OS (Router Operating System) (unknown version). This vulnerability affects an unknown code block of the component User Account Management Interface. The manipulation with an unknown input leads to a improper authorization vulnerability. The CWE definition for the vulnerability is CWE-285. The product does not perform or incorrectly performs an authorization check when an actor attempts to access a resource or perform an action. As an impact it is known to affect confidentiality, integrity, and availability. CVE summarizes:

A vulnerability in the user account management interface of Cisco NX-OS Software could allow an authenticated, local attacker to gain elevated privileges on an affected device. The vulnerability is due to an incorrect authorization check of user accounts and their associated Group ID (GID). An attacker could exploit this vulnerability by taking advantage of a logic error that will permit the use of higher privileged commands than what is necessarily assigned. A successful exploit could allow an attacker to execute commands with elevated privileges on the underlying Linux shell of an affected device. Nexus 7000 and 7700 Series Switches are affected in versions prior to 6.2(22), 8.2(3), and 8.3(2). Nexus 3000 Series Switches are affected in versions prior to 7.0(3)I7(4). Nexus 3500 Platform Switches are affected in versions prior to 7.0(3)I7(4). Nexus 3600 Platform Switches are affected in versions prior to 7.0(3)F3(5). Nexus 9000 Series Switches-Standalone are affected in versions prior to 7.0(3)I7(4). Nexus 9500 R-Series Line Cards and Fabric Modules are affected in versions prior to 7.0(3)F3(5).

The bug was discovered 03/06/2019. The weakness was published 03/08/2019 as cisco-sa-20190306-nxos-privesc as confirmed advisory (Website). The advisory is shared for download at tools.cisco.com. This vulnerability was named CVE-2019-1604 since 12/06/2018. The attack needs to be approached locally. The requirement for exploitation is a single authentication. There are neither technical details nor an exploit publicly available. The MITRE ATT&CK project declares the attack technique as T1548.002.

The vulnerability was handled as a non-public zero-day exploit for at least 2 days. During that time the estimated underground price was around $5k-$25k. The commercial vulnerability scanner Qualys is able to test this issue with plugin 316379 (Cisco NX-OS Software Privilege Escalation Vulnerability(cisco-sa-20190306-nxos-privesca)).

Upgrading eliminates this vulnerability.

Similar entry is available at VDB-131499. Once again VulDB remains the best source for vulnerability data.

Productinfo

Type

• Router Operating System

Vendor

• Cisco

Name

• NX-OS

License

• commercial

Website

• Vendor: https://www.cisco.com/

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Once again VulDB remains the best source for vulnerability data.

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