Legal Disclaimer

1. Nature of the Software

wM-Buster is a passive, receive-only research and educational tool for inspecting Wireless M-Bus traffic on the unlicensed 868 MHz Short Range Device (SRD) band. It does not transmit, jam, replay, spoof, or otherwise emit on the radio spectrum. It is intended for:

• The author's own metering equipment.
• Authorised security research with the operator's prior written consent.
• Educational study of the EN 13757 / OMS protocol stack.
• Validation of metering deployments by the responsible utility, property manager, or sub-meter operator.

2. Permitted Use

You may use this software only in jurisdictions and contexts in which its operation is lawful. You are solely responsible for determining whether that is the case for your specific situation. In particular:

• Reception of signals you are entitled to receive — for example, your own meter, where applicable national law gives you a statutory right of access to your consumption data (e.g. EU Directive 2018/2002 Art. 9–11).
• Authorised research with documented permission from the meter operator or the meter's owner.
• Possession and study of the software itself as protected expression (open-source / academic speech).

3. Prohibited Use

The author, contributors, and distributors expressly forbid and will not assist with any of the following:

• Decrypting or analysing telegrams from a meter that does not belong to you and for which you have no documented authorisation. In most jurisdictions this constitutes:
  • unlawful interception of private communications,
  • unlawful processing of personal data (GDPR Art. 6 / equivalents),
  • and/or theft-of-services / fraud where consumption data is used to estimate occupancy or to evade billing.
• Transmitting on the 868 MHz band using firmware modifications derived from this project. The on-device code path is RX-only and any TX capability would require a fork that the upstream maintainers do not endorse.
• Reverse-engineering or breaking the AES key infrastructure of a meter fleet you do not operate.
• Stalking, profiling, or surveilling individuals through their utility consumption patterns.
• Any other use prohibited by applicable law in your jurisdiction.

4. Radio Spectrum

The CC1101 transceiver in the Flipper Zero, including any external CC1101 module attached to its GPIO header, is licence-exempt under ETSI EN 300 220 (EU) and equivalent rules in other regions, for receive-only use within the 433 / 868 / 915 MHz SRD bands. wM-Buster does not move outside these constraints.

You are responsible for compliance with your local radio regulations (e.g. FCC Part 15, Industry Canada RSS-210, UK OFCOM IR 2030, etc.). If operation of the CC1101 is restricted in your jurisdiction even on receive, you must not run this software there.

5. AES Keys

Meter keys are typically printed on the installation document or made available through the property-management portal that operates the meter (Techem, ista, Kamstrup, etc.). Sharing them — even in a bug report — may expose the meter operator's customers to billing fraud and is almost always a violation of the meter-supply contract. The maintainers will delete and refuse any issue, pull request, or attachment that contains real keys, real meter IDs in clear, or decrypted telegrams from a meter that is not the contributor's own.

6. No Warranty

The software is provided "AS IS", without warranty of any kind. See sections 15–17 of the GNU GPL v3 for the full disclaimer of warranty and limitation of liability. The author and contributors are not liable for any direct, indirect, incidental, special, exemplary, or consequential damages arising from the use of, or inability to use, this software — including but not limited to civil or criminal liability arising from misuse, regulatory action, lost revenue, lost data, or hardware damage.

7. No Affiliation

wM-Buster is an independent open-source project. It is not affiliated with, endorsed by, or supported by:

• Flipper Devices Inc. or any Flipper Zero firmware distribution (mainline, Momentum, Unleashed, Xtreme, RogueMaster, etc.).
• Any meter manufacturer named in the source code, documentation, driver comments, or test fixtures (Techem, Kamstrup, Diehl, Engelmann, Sontex, BMeters, Apator, Zenner, Qundis, ista, Brunata, GWF, etc.). These names appear solely to identify the protocols the drivers decode, in compliance with nominative-fair-use principles.
• Any utility, metering authority, or property-management company.

8. Indemnification

By using or distributing wM-Buster you agree to indemnify and hold harmless the maintainers and contributors against any claim, demand, loss, liability, damage, fine, or expense (including reasonable legal fees) arising out of your use of the software in violation of this disclaimer or applicable law.

9. Reporting Misuse

If you become aware of someone using wM-Buster to attack a meter infrastructure they do not own, please report it to the meter operator and to the appropriate authority in your jurisdiction (national CERT, data-protection authority, or police). Do not open a public issue — that gives attackers a pre-built roadmap.

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This disclaimer is informational and does not constitute legal advice. Consult a qualified lawyer in your jurisdiction if you are unsure whether a specific use is lawful.