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CVE-2017-3853: Cisco Iox: Authentication bypass

CVE-2017-3853 is rated critical with a CVSS v3.0 base score of 9.8 and affects Cisco Iox. Per its scoring, it can be exploited over the network, without authentication, without any user interaction. The scored impact on confidentiality, integrity and availability is the highest available.

Vulnerability description

A vulnerability in the Data-in-Motion (DMo) process installed with the Cisco IOx application environment could allow an unauthenticated, remote attacker to cause a stack overflow that could allow remote code execution with root privileges in the virtual instance running on an affected device. The vulnerability is due to insufficient bounds checking in the DMo process. An attacker could exploit this vulnerability by sending crafted packets that are forwarded to the DMo process for evaluation. The impacts of a successful exploit are limited to the scope of the virtual instance and do not impact the router that is hosting Cisco IOx. This vulnerability affects the following Cisco 800 Series Industrial Integrated Services Routers: Cisco IR809 and Cisco IR829. Cisco IOx Releases 1.0.0.0 and 1.1.0.0 are vulnerable. Cisco Bug IDs: CSCuy52330.

Severity breakdown

CVSS v3.0 9.8: CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/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: 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: High. Total loss of availability; the component can be shut down.

Underlying weakness

CWE-119: Improper Restriction of Operations within the Bounds of a Memory Buffer

The product performs operations on a memory buffer, but it reads from or writes to a memory location outside the buffer's intended boundary.

Affected products

  • Cisco Iox: 1.1\(0\); 1.1.0

References