A vulnerability, which was classified as problematic, was found in Cisco NX-OS (Router Operating System) (the affected version unknown). This affects an unknown part of the component SSH CLI Key Management. The manipulation with an unknown input leads to a information disclosure vulnerability. CWE is classifying the issue as CWE-200. The product exposes sensitive information to an actor that is not explicitly authorized to have access to that information. This is going to have an impact on confidentiality. The summary by CVE is:

A vulnerability in the SSH CLI key management functionality of Cisco NX-OS Software could allow an authenticated, local attacker to expose a user's private SSH key to all authenticated users on the targeted device. The attacker must authenticate with valid administrator device credentials. The vulnerability is due to incomplete error handling if a specific error type occurs during the SSH key export. An attacker could exploit this vulnerability by authenticating to the device and entering a crafted command at the CLI. A successful exploit could allow the attacker to expose a user's private SSH key. In addition, a similar type of error in the SSH key import could cause the passphrase-protected private SSH key to be imported unintentionally.

The bug was discovered 05/15/2019. The weakness was published 05/15/2019 as cisco-sa-20190515-nxos-ssh-inf as confirmed advisory (Website). It is possible to read the advisory at tools.cisco.com. This vulnerability is uniquely identified as CVE-2019-1731 since 12/06/2018. Attacking locally is a requirement. A authentication is necessary for exploitation. The technical details are unknown and an exploit is not publicly available. The pricing for an exploit might be around USD $0-$5k at the moment (estimation calculated on 09/19/2023). The attack technique deployed by this issue is T1592 according to MITRE ATT&CK.

The commercial vulnerability scanner Qualys is able to test this issue with plugin 316461 (Cisco NX-OS Software SSH Key Information Disclosure Vulnerability(cisco-sa-20190515-nxos-ssh-info)).

There is no information about possible countermeasures known. It may be suggested to replace the affected object with an alternative product.

Productinfo

Type

• Router Operating System

Vendor

• Cisco

Name

• NX-OS

License

• commercial

CPE 2.3info

• 🔍

CPE 2.2info

• 🔍

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