Security
Privacy and crypto
With digital assets, privacy is not a luxury but a security layer. Every time you leave an email address, phone number or home address with a crypto-related service, the odds grow that this data ends up in a breach. The blockchain does not leak; the companies around it do. This is education, not investment advice.
Why breaches are dangerous
A platform breach rarely contains keys. It contains names, addresses, phone numbers and sometimes balances or purchase history — a shopping list for scammers.
The follow-up attack is almost always social: an email naming your exact platform, a text about a 'suspicious withdrawal', a call from someone who knows your purchase amount.
You cannot prevent a third party breach. You can decide how much of you is in it.
- Use a unique email address or alias per service
- Never publish balances, screenshots or purchase amounts
- Treat your phone number as sensitive data, not as a login
Four layers of digital hygiene
Privacy works in layers. Each layer makes profiling you more expensive. Start with the layer that leaks most: usually email.
Build privacy in four steps
- 01
1. Separate email
An encrypted address used nowhere else
- 02
2. Unique passwords
Password manager, no reuse
- 03
3. 2FA without SMS
Authenticator app or hardware key
- 04
4. Network and device
VPN on public wifi, updates, disk encryption
Metadata: what you reveal without words
A blockchain address you share publicly once links your name to your transaction history forever.
The same applies offline: branded hardware wallet packaging, photos with visible equipment, a profile naming your role in the sector.
Use a fresh address per payer and keep a separate wallet for publicly shared addresses.
- Share addresses privately
- Avoid branded packaging for sensitive hardware
- Separate a public wallet from your savings wallet
What privacy is not
Privacy is not anonymity and never a way to dodge rules. KYC stays mandatory at European exchanges.
The more privacy you build, the more important your recovery plan becomes.
Recommended by our newsroom
External parties. Block #9 does not hold or manage your assets at these providers. Not investment advice.
Frequently asked questions
Do I need a VPN to buy crypto?
Not strictly, but on public wifi it is wise. Note that some exchanges block logins from foreign VPN servers.
Can I use an alias email at an exchange?
Yes. The email may differ; your identity during KYC must be accurate.
Which privacy provider do you recommend?
We use Proton for email, VPN, storage and passwords, under Swiss privacy law and encrypted by default.
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