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CVE-2017-5159: Phoenixcontact Mguard Firmware: Improper Control of Resource Identifiers

CVE-2017-5159 is rated critical with a CVSS v3.1 base score of 9.8 and NVD lists Phoenixcontact Mguard Firmware as the affected product. 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

An issue was discovered on Phoenix Contact mGuard devices that have been updated to Version 8.4.0. When updating an mGuard device to Version 8.4.0 via the update-upload facility, the update will succeed, but it will reset the password of the admin user to its default value.

Severity breakdown

CVSS v3.1 9.8: CVSS:3.1/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-99: Improper Control of Resource Identifiers

The product receives input from an upstream component, but it does not restrict or incorrectly restricts the input before it is used as an identifier for a resource that may be outside the intended control sphere.

Affected products

  • Phoenixcontact Mguard Firmware: 8.4.0

References