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CVE-2017-6711: Cisco Ultra Services Framework: Authentication bypass

CVE-2017-6711 is rated critical with a CVSS v3.0 base score of 9.1 and affects Cisco Ultra Services Framework. Per its scoring, it can be exploited over the network, without authentication, without any user interaction.

Vulnerability description

A vulnerability in the Ultra Automation Service (UAS) of the Cisco Ultra Services Framework could allow an unauthenticated, remote attacker to gain unauthorized access to a targeted device. The vulnerability is due to an insecure default configuration of the Apache ZooKeeper service used by the affected software. An attacker could exploit this vulnerability by accessing the affected device through the orchestrator network. An exploit could allow the attacker to gain access to ZooKeeper data nodes (znodes) and influence the behavior of the system's high-availability feature. This vulnerability affects all releases of Cisco Ultra Services Framework UAS prior to Releases 5.0.3 and 5.1. Cisco Bug IDs: CSCvd29395.

Severity breakdown

CVSS v3.0 9.1: CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N

  • 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: None. No account or prior access is needed.
  • User interaction: None. No action from any user is needed.
  • Scope: Unchanged. Impact stays within the vulnerable component.
  • 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: None. No effect on availability.

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 Ultra Services Framework: up to and including 5.0.2

References