CVE Vulnerabilities

CVE-2019-1731

Exposure of Sensitive Information to an Unauthorized Actor

Published: May 15, 2019 | Modified: Nov 21, 2024
CVSS 3.x
4.4
MEDIUM
Source:
NVD
CVSS:3.1/AV:L/AC:L/PR:H/UI:N/S:U/C:H/I:N/A:N
CVSS 2.x
2.1 LOW
AV:L/AC:L/Au:N/C:P/I:N/A:N
RedHat/V2
RedHat/V3
Ubuntu

A vulnerability in the SSH CLI key management functionality of Cisco NX-OS Software could allow an authenticated, local attacker to expose a users 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 users 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.

Weakness

The product exposes sensitive information to an actor that is not explicitly authorized to have access to that information.

Affected Software

Name Vendor Start Version End Version
Nx-os Cisco * 7.0(3)i4(9) (excluding)
Nx-os Cisco 7.0(3)i7 (including) 7.0(3)i7(4) (excluding)

Extended Description

There are many different kinds of mistakes that introduce information exposures. The severity of the error can range widely, depending on the context in which the product operates, the type of sensitive information that is revealed, and the benefits it may provide to an attacker. Some kinds of sensitive information include:

Information might be sensitive to different parties, each of which may have their own expectations for whether the information should be protected. These parties include:

Information exposures can occur in different ways:

It is common practice to describe any loss of confidentiality as an “information exposure,” but this can lead to overuse of CWE-200 in CWE mapping. From the CWE perspective, loss of confidentiality is a technical impact that can arise from dozens of different weaknesses, such as insecure file permissions or out-of-bounds read. CWE-200 and its lower-level descendants are intended to cover the mistakes that occur in behaviors that explicitly manage, store, transfer, or cleanse sensitive information.

Potential Mitigations

  • Compartmentalize the system to have “safe” areas where trust boundaries can be unambiguously drawn. Do not allow sensitive data to go outside of the trust boundary and always be careful when interfacing with a compartment outside of the safe area.
  • Ensure that appropriate compartmentalization is built into the system design, and the compartmentalization allows for and reinforces privilege separation functionality. Architects and designers should rely on the principle of least privilege to decide the appropriate time to use privileges and the time to drop privileges.

References