OTPulse

Siemens SIMATIC WinCC Vulnerabilities (Update A)

Low RiskICS-CERT ICSA-14-205-02AApr 26, 2014
Siemens
Summary

SIMATIC WinCC versions prior to 7.3 and SIMATIC PCS7 versions prior to 8.1 contain multiple vulnerabilities related to authentication bypass, insecure session handling, insufficient access controls, and exposure of sensitive information. These vulnerabilities could allow an attacker with network access to the HMI interface to bypass authentication, intercept or modify data, or escalate privileges. The vulnerabilities stem from improper input validation, inadequate session management, and weak access control mechanisms. No patches have been released by Siemens for these products.

What this means
What could happen
An attacker with network access to SIMATIC WinCC could obtain sensitive information or gain unauthorized control over the HMI, potentially allowing manipulation of displayed process data or alteration of operator-accessible functions that may affect plant operations.
Who's at risk
Water utilities and electric utilities operating SIMATIC WinCC HMI (Human Machine Interface) systems version 7.3 and earlier, and SIMATIC PCS7 (Process Control System 7) version 8.1 and earlier. This affects the operator interface and data management layer for industrial control systems managing critical plant operations.
How it could be exploited
An attacker could exploit authentication bypass, insecure data handling, or insufficient access controls to reach the WinCC HMI interface without proper credentials. Once inside, they could read configuration files, modify process setpoints visible in the operator interface, or disable safety-related displays.
Prerequisites
  • Network access to WinCC HMI port (typically 80/HTTP or 443/HTTPS)
  • Knowledge of WinCC interface or default paths
  • No valid credentials required if authentication bypass vulnerabilities are exploited
remotely exploitableinsufficient access controlsno patch availablemultiple attack vectors (CWE-425: untrusted data, CWE-384: session fixation, CWE-269: improper handling of privileges, CWE-284: access control failures, CWE-321: sensitive data exposure)
Exploitability
Unlikely to be exploited — EPSS score 0.4%
Affected products (2)
2 with fix
ProductAffected VersionsFix Status
SIMATIC WinCC: <7.3<7.37.3+
SIMATIC PCS7 (as WinCC is incorporated): <8.1<8.18.1+
Remediation & Mitigation
0/5
Do now
0/3
HARDENINGIsolate SIMATIC WinCC and PCS7 systems from untrusted networks using firewall rules; restrict access to engineering workstations and authorized operator stations only
HARDENINGImplement network segmentation to separate HMI systems from corporate network and internet-facing systems
WORKAROUNDDisable unused WinCC services and network ports to reduce attack surface
Schedule — requires maintenance window
0/2

Patching may require device reboot — plan for process interruption

HARDENINGMonitor WinCC systems for unauthorized access attempts and configuration changes
HARDENINGMaintain regular backups of WinCC configurations to enable rapid recovery if systems are compromised
View full CISA ICS-CERT advisory
API: /api/v1/advisories/c07588bf-dac0-4d8a-910f-e47b7df0c160

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Siemens SIMATIC WinCC Vulnerabilities (Update A) - OTPulse