performing-s7comm-protocol-security-analysis

# Performing S7comm Protocol Security Analysis ## When to Use - When assessing the security posture of Siemens SIMATIC S7 PLC environments - When building detection rules for S7comm-based attacks against S7-300/400/1200/1500 controllers - When performing a security audit of Siemens Step 7/TIA Portal communications - When investigating suspected unauthorized access to Siemens PLC programs - When evaluating S7CommPlus integrity mechanisms and their bypass potential **Do not use** for scanning production Siemens PLCs without authorization and a test plan (this can crash controllers), for non-Siemens protocol analysis (see detecting-modbus-command-injection-attacks for Modbus), or for modifying PLC programs in a production environment. ## Prerequisites - Network access to the S7comm communication segment (TCP port 102) - Wireshark with S7comm dissector or Zeek with S7comm protocol analyzer - Authorized access for security testing (never scan production PLCs without authorization) - Knowledge of the Siemens PLC models and firmware versions in scope - Understanding of S7comm protocol structure (COTP, S7 PDU, function codes) ## Workflow ### Step 1: Analyze S7comm Traffic and Identify Vulnerabilities ```python #!/usr/bin/env python3 """S7comm Protocol Security Analyzer. Analyzes Siemens S7comm protocol traffic to identify security vulnerabilities, unauthorized access patterns, and potential attack indicators against SIMATIC S7 PLCs. """ import struct import sys import json ...