Siemens WinCC 7.0 SP3 Multiple Vulnerabilities
Low RiskICS-CERT ICSA-13-079-02Dec 22, 2013
Summary
Siemens WinCC 7.0 SP3 and earlier versions contain multiple vulnerabilities affecting buffer handling (CWE-119), access control (CWE-285), sensitive data transmission (CWE-311), and path traversal (CWE-23). These issues may allow unauthorized access, information disclosure, or code execution on the HMI/SCADA monitoring system.
What this means
What could happen
An attacker with network access to WinCC could gain unauthorized access to the human-machine interface, potentially view sensitive process data or modify process setpoints without authorization, disrupting industrial operations.
Who's at risk
Water utilities, electric utilities, and other critical infrastructure operators using Siemens WinCC 7.0 SP3 or earlier for SCADA monitoring and operator interface should evaluate their exposure. WinCC is commonly used as the HMI layer monitoring process values, trends, alarms, and operator controls on PLCs and remote terminal units (RTUs).
How it could be exploited
An attacker on the network could exploit the access control and buffer overflow vulnerabilities to bypass authentication or crash the WinCC service. Path traversal could allow reading sensitive configuration files or logs that reveal plant process information. Buffer overflow in certain input handlers could allow remote code execution on the monitoring workstation.
Prerequisites
- Network access to the WinCC host on the default or configured service ports
- WinCC service must be running and accessible
- No valid credentials required for some vulnerabilities
remotely exploitableno authentication required for some attack pathsno patch availableaffects monitoring and control systems
Exploitability
Moderate exploit probability (EPSS 2.7%)
Affected products (1)
ProductAffected VersionsFix Status
WinCC: <=7.0_SP3_Update1≤ 7.0 SP3 Update1No fix (EOL)
Remediation & Mitigation
0/5
Do now
0/2HARDENINGRestrict network access to WinCC hosts: implement firewall rules to limit inbound connections to the HMI workstations to authorized engineering and monitoring stations only, blocking internet-facing access
WORKAROUNDDisable unused WinCC services and remote access features if not required for operations
Schedule — requires maintenance window
0/2Patching may require device reboot — plan for process interruption
HARDENINGIsolate WinCC monitoring workstations on a separate industrial network segment (VLAN) with access controls between the control network and corporate IT network
HARDENINGMonitor WinCC logs and system resources for signs of exploitation (unexpected process crashes, failed authentication attempts, unusual file access patterns)
Long-term hardening
0/1HOTFIXPlan migration to WinCC 7.4 or later (supported versions with security patches) as a long-term measure
↑↓ Navigate · Esc Close
API:
/api/v1/advisories/9e46bd09-3434-4841-bd8a-bc79e2a1fc45