OTPulse

Schneider Electric SoMachine HVAC Unsafe ActiveX Control Vulnerability

MonitorCVSS 7.3ICS-CERT ICSA-16-196-03Apr 17, 2016
Schneider ElectricEnergy
Attack path
Attack VectorNetwork
Auth RequiredNone
ComplexityLow
User InteractionNone needed
Summary

Unsafe ActiveX control vulnerability in Schneider Electric SoMachine HVAC-Application versions 2.0.2 and earlier. The vulnerability allows remote code execution through a malicious webpage or document if a user opens it in Internet Explorer or a browser with ActiveX support. The ActiveX control does not properly validate inputs, allowing an attacker to execute arbitrary code with the privileges of the logged-in user. Affected versions are SoMachine HVAC-Application 2.0.2 and earlier. No patch is available from Schneider Electric.

What this means
What could happen
An attacker could run arbitrary code on a Windows workstation running SoMachine HVAC-Application, potentially allowing them to modify HVAC control logic, alter setpoints, or shut down climate control systems that may be critical to facility operations.
Who's at risk
HVAC operators and facilities managers at energy utilities and buildings using Schneider Electric SoMachine HVAC-Application for climate control system management. This includes any facility relying on SoMachine HVAC for automated heating, ventilation, and air conditioning control, particularly data centers, control rooms, and critical infrastructure where temperature regulation is essential to operations.
How it could be exploited
An attacker would need to get a Windows user on the SoMachine workstation to open a malicious web page or document containing the unsafe ActiveX control. The vulnerable control would execute with the privileges of the logged-in user, allowing the attacker to run arbitrary code on that machine and potentially spread to connected systems.
Prerequisites
  • User at SoMachine HVAC workstation must open a malicious webpage or document in Internet Explorer or embedded browser
  • SoMachine HVAC-Application version 2.0.2 or earlier must be installed
  • Internet Explorer or legacy browser with ActiveX support must be in use
remotely exploitableno authentication requiredlow complexityno patch availableaffects facility operations systems
Exploitability
Some exploitation risk — EPSS score 4.3%
Affected products (1)
ProductAffected VersionsFix Status
SoMachine HVAC-Application: <=2.0.2≤ 2.0.2No fix (EOL)
Remediation & Mitigation
0/5
Do now
0/1
WORKAROUNDBlock or disable ActiveX controls on Windows workstations running SoMachine HVAC-Application via Group Policy or browser security settings
Schedule — requires maintenance window
0/1

Patching may require device reboot — plan for process interruption

HARDENINGConfigure Windows Defender SmartScreen and keep Windows Defender up to date on all SoMachine HVAC workstations
Mitigations - no patch available
0/3
SoMachine HVAC-Application: <=2.0.2 has reached End of Life. The vendor will not release a patch. Apply the following compensating controls:
HARDENINGImplement network segmentation to isolate SoMachine HVAC workstations from general office networks and untrusted internet access
HARDENINGRestrict user access on SoMachine HVAC workstations to run only necessary applications; remove or limit web browsing capability from engineering workstations
HARDENINGImplement email filtering and web content filtering to block known malicious domains and attachments from reaching SoMachine HVAC workstations
View full CISA ICS-CERT advisory
API: /api/v1/advisories/b357a78c-bc0f-494c-9b22-a3a6cad312f5

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