OTPulse

Siemens SICAM A8000 Devices

Plan PatchCVSS 7.2ICS-CERT ICSA-23-166-13Jun 13, 2023
Siemens
Attack path
Attack VectorNetwork
Auth RequiredHigh
ComplexityLow
User InteractionNone needed
Summary

The CPCI85 firmware of Siemens SICAM A8000 CP-8031 and CP-8050 master modules contains multiple vulnerabilities: (1) authenticated remote command injection allowing arbitrary code execution on the device, (2) exposure of the serial UART debug interface accessible from the network, and (3) hardcoded credentials for UART login. These master modules are used for grid-level protection and monitoring in electrical substations and control centers. Exploitation could allow an attacker to manipulate grid control parameters, interfere with protection logic, or disable critical monitoring functions.

What this means
What could happen
An attacker with engineering credentials could inject remote commands on SICAM A8000 master modules, potentially altering grid control parameters or interrupting substation protection and monitoring functions. Additionally, hardcoded credentials on the UART debug interface allow direct physical or network-proxied access to the device, bypassing normal security controls.
Who's at risk
Operators of electrical transmission and distribution networks (TSOs, DSOs, substations) using Siemens SICAM A8000 CP-8031 and CP-8050 master modules for grid monitoring, control, and secondary protection. These are critical protection and control devices in the power grid; compromise could impact fault detection and response.
How it could be exploited
An attacker with valid engineering workstation credentials could authenticate to the SICAM A8000 CP-8031 or CP-8050 master module via the network management interface and inject malicious commands into the CPCI85 firmware, gaining code execution on the device. Alternatively, an attacker with physical access to the device or network access to the exposed UART serial interface could use hardcoded credentials to bypass authentication and execute arbitrary commands directly on the master module.
Prerequisites
  • Valid engineering credentials for the SICAM A8000 management interface (for authenticated remote command injection)
  • Network connectivity to the management port of the CP-8031 or CP-8050 master module
  • Physical access to the UART debug port OR network path to the exposed UART interface for the hardcoded credential attack
remotely exploitablehigh EPSS score (11.7%)high CVSS (7.2)authenticated command injectionhardcoded credentialsno patch available for firmware versions below CPCI85 V05
Exploitability
Some exploitation risk — EPSS score 9.8%
Affected products (2)
2 with fix
ProductAffected VersionsFix Status
CP-8031 MASTER MODULE (6MF2803-1AA00)<vers:/ CPCI85 V05CPCI85 V05+
CP-8050 MASTER MODULE (6MF2805-0AA00)<vers:/ CPCI85 V05CPCI85 V05+
Remediation & Mitigation
0/6
Do now
0/2
WORKAROUNDDisable or physically restrict access to the UART debug serial interface on both CP-8031 and CP-8050 modules until firmware update can be applied
HARDENINGRestrict network access to the SICAM A8000 management interfaces using firewall rules; segment the substation network from corporate IT and untrusted networks
Schedule — requires maintenance window
0/2

Patching may require device reboot — plan for process interruption

CP-8050 MASTER MODULE (6MF2805-0AA00)
HOTFIXUpdate CP-8050 MASTER MODULE (6MF2805-0AA00) to CPCI85 V05 or later version
CP-8031 MASTER MODULE (6MF2803-1AA00)
HOTFIXUpdate CP-8031 MASTER MODULE (6MF2803-1AA00) to CPCI85 V05 or later version
Long-term hardening
0/2
HARDENINGImplement VPN or other encrypted tunneling for any remote engineering access to SICAM A8000 devices
HARDENINGReview and rotate engineering credentials for SICAM A8000 systems; enforce strong password policies and multi-factor authentication where supported
View full CISA ICS-CERT advisory
API: /api/v1/advisories/03ebd566-ae9b-4cc3-9a56-f133d16c553f

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