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CVE-2017-12739: Siemens Sm 2556 Firmware: Authentication bypass

CVE-2017-12739 is rated critical with a CVSS v3.0 base score of 9.8 and NVD lists Siemens Sm 2556 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 Siemens SICAM RTUs SM-2556 COM Modules with the firmware variants ENOS00, ERAC00, ETA2, ETLS00, MODi00, and DNPi00. The integrated web server (port 80/tcp) of the affected devices could allow unauthenticated remote attackers to execute arbitrary code on the affected device.

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-1188: Initialization of a Resource with an Insecure Default

The product initializes or sets a resource with a default that is intended to be changed by the product's installer, administrator, or maintainer, but the default is not secure.

Affected products

  • Siemens Sm 2556 Firmware: dnpi00; enos00; erac00; eta2; etls00; modi00

References