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CVE-2018-7846: A CWE-501: Trust Boundary Violation vulnerability on connection to the Controller exists in all versions of…

CVE-2018-7846 is rated critical with a CVSS v3.1 base score of 9.8 and NVD lists 4 affected products, including Schneider Electric Modicon M580 Firmware. 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 CWE-501: Trust Boundary Violation vulnerability on connection to the Controller exists in all versions of the Modicon M580, Modicon M340, Modicon Quantum and Modicon Premium which could cause unauthorized access by conducting a brute force attack on Modbus protocol to the controller.

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-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

  • Schneider Electric Modicon M580 Firmware: all versions listed by NVD
  • Schneider Electric Modicon M340 Firmware: all versions listed by NVD
  • Schneider Electric Modicon Quantum Firmware: all versions listed by NVD
  • Schneider Electric Modicon Premium Firmware: all versions listed by NVD

References