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CVE-2017-12249: Cisco Meeting Server: Authentication bypass

CVE-2017-12249 is rated critical with a CVSS v3.0 base score of 9.1 and affects Cisco Meeting Server. 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 Traversal Using Relay NAT (TURN) server included with Cisco Meeting Server (CMS) could allow an authenticated, remote attacker to gain unauthenticated or unauthorized access to components of or sensitive information in an affected system. The vulnerability is due to an incorrect default configuration of the TURN server, which could expose internal interfaces and ports on the external interface of an affected system. An attacker could exploit this vulnerability by using a TURN server to perform an unauthorized connection to a Call Bridge, a Web Bridge, or a database cluster in an affected system, depending on the deployment model and CMS services in use. A successful exploit could allow the attacker to gain unauthenticated access to a Call Bridge or database cluster in an affected system or gain unauthorized access to sensitive meeting information in an affected system. To exploit this vulnerability, the attacker must have valid credentials for the TURN server of the affected system. This vulnerability affects Cisco Meeting Server (CMS) deployments that are running a CMS Software release prior to Release 2.0.16, 2.1.11, or 2.2.6. Cisco Bug IDs: CSCvf51127.

Severity breakdown

CVSS v3.0 9.1: CVSS:3.0/AV:N/AC:L/PR:H/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: High. Administrative-level privileges are needed.
  • 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-668: Exposure of Resource to Wrong Sphere

The product exposes a resource to the wrong control sphere, providing unintended actors with inappropriate access to the resource.

Affected products

  • Cisco Meeting Server: up to and including 2.0.15; 2.1.0; 2.1.1; 2.1.2; 2.1.3; 2.1.4; 2.1.5; 2.1.6; 2.1.7; 2.1.8; 2.1.9; 2.1.10

References