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detecting-modbus-protocol-anomalies

85 / 100 · Low risk

Fine to try.

By plurigrid/asi (GitHub) · coding · 72 stars · scanned at commit 293ce9f

This skill covers detecting anomalies in Modbus/TCP and Modbus RTU communications in industrial control systems. It addresses function code monitoring, register range validation, timing analysis, unauthorized client detection, and deep packet inspection for malformed Modbus frames. The skill leverages Zeek with Modbus protocol analyzers, Suricata IDS with OT rules, and custom Python-based detection using Markov chain models for normal Modbus transaction sequences.

Works with any agent that supports SKILL.md skills.

What this skill can do

Install

Paste this into your terminal. It downloads exactly the version we scanned, not whatever is newest.

if [ -e ~/.agents/skills/'detecting-modbus-protocol-anomalies' ] || [ -L ~/.agents/skills/'detecting-modbus-protocol-anomalies' ]; then echo 'A skill folder named detecting-modbus-protocol-anomalies already exists — not replacing it' >&2; false; else d=$(mktemp -d) && git clone --quiet --filter=blob:none --no-checkout 'https://github.com/plurigrid/asi' "$d" && git -C "$d" checkout --quiet '293ce9f76e3abcd5ba18db284688bc0d9ac6691d' -- 'plugins/asi/skills/detecting-modbus-protocol-anomalies' && mkdir -p ~/.agents/skills && cp -R "$d"/'plugins/asi/skills/detecting-modbus-protocol-anomalies' ~/.agents/skills/'detecting-modbus-protocol-anomalies' && rm -rf "$d"; fi

Codex reads ~/.agents/skills directly. For Claude Code, Cursor, Copilot, Gemini CLI, Antigravity or OpenCode, also link it. For Claude Code: ln -s ~/.agents/skills/'detecting-modbus-protocol-anomalies' ~/.claude/skills/'detecting-modbus-protocol-anomalies' (other agents: ~/.cursor/skills, ~/.copilot/skills, ~/.gemini/skills, ~/.gemini/config/skills, ~/.config/opencode/skills). Or install through the finder skill, which does both.

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