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CVE-2018-0264: Cisco Webex Meeting Server: Authentication bypass

CVE-2018-0264 is rated critical with a CVSS v3.0 base score of 9.6 and affects Cisco Webex Meeting Server, along with 2 other products in NVD’s configuration data. Per its scoring, it can be exploited over the network, without authentication. The scored impact on confidentiality, integrity and availability is the highest available.

Vulnerability description

A vulnerability in the Cisco WebEx Network Recording Player for Advanced Recording Format (ARF) files could allow an unauthenticated, remote attacker to execute arbitrary code on the system of a targeted user. An attacker could exploit this vulnerability by sending the user a link or email attachment with a malicious ARF file and persuading the user to follow the link or open the file. Successful exploitation could allow the attacker to execute arbitrary code on the user's system. This vulnerability affects Cisco WebEx Business Suite meeting sites, Cisco WebEx Meetings sites, Cisco WebEx Meetings Server, and Cisco WebEx ARF players. The following client builds of Cisco WebEx Business Suite (WBS31 and WBS32), Cisco WebEx Meetings, and Cisco WebEx Meetings Server are affected: Cisco WebEx Business Suite (WBS31) client builds prior to T31.23.4, Cisco WebEx Business Suite (WBS32) client builds prior to T32.12, Cisco WebEx Meetings with client builds prior to T32.12, Cisco WebEx Meeting Server builds prior to 3.0 Patch 1. Cisco Bug IDs: CSCvh85410, CSCvh85430, CSCvh85440, CSCvh85442, CSCvh85453, CSCvh85457.

Severity breakdown

CVSS v3.0 9.6: CVSS:3.0/AV:N/AC:L/PR:N/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: None. No account or prior access is needed.
  • 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 Meeting Server: before 3.0
  • Cisco Webex Meetings: before t32.12
  • Cisco Webex Business Suite 31: before t32.12
  • Cisco Webex Business Suite 32: before t31.23.4

References