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CVE-2018-0112: Cisco Webex Meetings Server: Remote code execution

CVE-2018-0112 is rated critical with a CVSS v3.0 base score of 9.0 and affects Cisco Webex Meetings Server, along with 2 other products in NVD’s configuration data. Per its scoring, it can be exploited over the network. The scored impact on confidentiality, integrity and availability is the highest available.

Vulnerability description

A vulnerability in Cisco WebEx Business Suite clients, Cisco WebEx Meetings, and Cisco WebEx Meetings Server could allow an authenticated, remote attacker to execute arbitrary code on a targeted system. The vulnerability is due to insufficient input validation by the Cisco WebEx clients. An attacker could exploit this vulnerability by providing meeting attendees with a malicious Flash (.swf) file via the file-sharing capabilities of the client. Exploitation of this vulnerability could allow arbitrary code execution on the system of a targeted user. This affects the clients installed by customers when accessing a WebEx meeting. The following client builds of Cisco WebEx Business Suite (WBS30, WBS31, and WBS32), Cisco WebEx Meetings, and Cisco WebEx Meetings Server are impacted: Cisco WebEx Business Suite (WBS31) client builds prior to T31.23.2, Cisco WebEx Business Suite (WBS32) client builds prior to T32.10, Cisco WebEx Meetings with client builds prior to T32.10, Cisco WebEx Meetings Server builds prior to 2.8 MR2. Cisco Bug IDs: CSCvg19384, CSCvi10746.

Severity breakdown

CVSS v3.0 9.0: CVSS:3.0/AV:N/AC:L/PR:L/UI:R/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: Required. A user must take an action, such as opening a file or following a link.
  • 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-20: Improper Input Validation

The product receives input or data, but it does not validate or incorrectly validates that the input has the properties that are required to process the data safely and correctly.

Affected products

  • Cisco Webex Meetings Server: 2.7; 2.8; 3.0
  • Cisco Webex Meetings: t31; t31 sp11
  • Cisco Webex Business Suite 31: before t31.23.2
  • Cisco Webex Business Suite 32: before t32.10

References