Security & Self-Custody

1. The Concept of Self-Custody

In traditional finance, banks hold your money and verify your identity. If you lose your password, they can reset it. In Web3, Self-Custody means you hold the cryptographic keys to your assets on the blockchain. You are your own bank. Consequently, if you lose your private keys or seed phrase, there is no customer support to restore your access—your assets are lost permanently.

2. Seed Phrases and Private Keys

When you create a crypto wallet, you are provided with a Seed Phrase (usually 12 or 24 random English words). This phrase mathematically generates all the private keys for your wallets across different networks.

• Rule 1: Never type your seed phrase into a website.
• Rule 2: Never store your seed phrase digitally (e.g., screenshots, notes apps, cloud storage). Keep it written on physical paper or metal and store it securely.
• Rule 3: Anyone who obtains your seed phrase has complete control over your assets. Treat it like a master key to a vault.

3. Hardware Wallets vs. Hot Wallets

A "Hot Wallet" (like a browser extension) is connected to the internet, making it convenient but vulnerable to malware. A "Hardware Wallet" (a physical USB-like device) stores your private keys entirely offline. When you transact, you physically approve it on the device, meaning hackers cannot steal your keys via the internet.

4. Phishing and Smart Contract Risks

The majority of lost funds in Web3 are NOT from blockchains being hacked, but from users being tricked into handing over their keys or approving malicious transactions.

Malicious Approvals: When using DeFi, you must grant smart contracts permission to interact with your wallet. If you connect to a fake or compromised website, you might accidentally sign an approval that allows the attacker to drain your assets. Always verify URLs, never click links in direct messages, and revoke smart contract approvals when not actively trading.