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CVE-2018-0238: Cisco Unified Computing System Director: Improper Authentication

CVE-2018-0238 is rated critical with a CVSS v3.0 base score of 9.9 and NVD lists Cisco Unified Computing System Director as the affected product. Per its scoring, it can be exploited over the network, without any user interaction. The scored impact on confidentiality, integrity and availability is the highest available.

Vulnerability description

A vulnerability in the role-based resource checking functionality of the Cisco Unified Computing System (UCS) Director could allow an authenticated, remote attacker to view unauthorized information for any virtual machine in the UCS Director end-user portal and perform any permitted operations on any virtual machine. The permitted operations can be configured for the end user on the virtual machines with either of the following settings: The virtual machine is associated to a Virtual Data Center (VDC) that has an end user self-service policy attached to the VDC. The end user role has VM Management Actions settings configured under User Permissions. This is a global configuration, so all the virtual machines visible in the end-user portal will have the VM management actions available. The vulnerability is due to improper user authentication checks. An attacker could exploit this vulnerability by logging in to the UCS Director with a modified username and valid password. A successful exploit could allow the attacker to gain visibility into and perform actions against all virtual machines in the UCS Director end-user portal of the affected system. This vulnerability affects Cisco Unified Computing System (UCS) Director releases 6.0 and 6.5 prior to patch 3 that are in a default configuration. Cisco Bug IDs: CSCvh53501.

Severity breakdown

CVSS v3.0 9.9: CVSS:3.0/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H

  • Attack vector: Network. Exploitable remotely over the network, with no need for local or physical access.
  • Attack complexity: Low. No special conditions; the attack can be repeated reliably.
  • Privileges required: Low. A basic user account is enough.
  • User interaction: None. No action from any user is needed.
  • Scope: Changed. Impact reaches beyond the vulnerable component to other resources.
  • Confidentiality impact: High. Total loss of confidentiality; sensitive data can be fully disclosed.
  • Integrity impact: High. Total loss of integrity; data or system state can be fully modified.
  • Availability impact: High. Total loss of availability; the component can be shut down.

Underlying weakness

CWE-287: Improper Authentication

When an actor claims to have a given identity, the product does not prove or insufficiently proves that the claim is correct.

Affected products

  • Cisco Unified Computing System Director: 6.5\(0.0\); 6.5\(0.1\)

References