Beginner20–25 minLesson 5

Security by default: 2FA, Seed, Phishing, Approvals, Hardware

In 30 minutes you'll set key protections and assemble your personal Security Playbook. Never share secrets here — nothing is collected.

Lesson Progress0%
What you will learn
  • Enable TOTP 2FA and a withdrawal allowlist on your exchange.
  • Organize an offline seed backup and understand when to add a passphrase.
  • Spot phishing instantly and avoid address poisoning traps.
  • Review and revoke risky DeFi token approvals.
  • Set up a hardware wallet for larger holdings and verify addresses on-device.

5.1Exchange security

Most account breaches start with weak passwords or SMS codes. Switch to TOTP, lock withdrawals, and reduce human error.

TOTP 2FA (not SMS)

Use an authenticator (Aegis, Authy, 1Password/Bitwarden). Save backup codes offline. SMS is vulnerable to SIM-swap — use TOTP only.

Withdrawal allowlist

Add your own wallets and enforce a 24–48h delay for new addresses. Unlisted withdrawals get blocked.

Anti-phishing code

Set a personal code shown in official emails. If the code is missing, treat it as a red flag.

Unique passwords + manager

One service — one password, 16+ chars. Store in a password manager, not browser notes.

5.2Self-custody: seed and passphrase

Your seed is the wallet. Keep it offline and resilient.

Right

  • Offline paper/metal backup
  • Two copies in separate locations
  • Non-obvious labeling

Wrong

  • Cloud storage / email
  • Screenshots / photos
  • Single copy in one location

Offline seed backup

Handwrite clearly. Make two copies, store in separate safe locations. No photos, scans, or cloud.

Passphrase (if supported)

An extra word on top of the seed creates a new wallet. Losing the passphrase means losing access to that wallet. Use for a hidden layer if you can maintain it.

Hidden backup strategies

Split storage across locations, consider fireproof metal plates, use non-obvious labeling so a stranger can't reconstruct it.

No screenshots

Any image is an online copy; phone/cloud leaks leak your seed.

5.3Phishing

A "nearly correct" link is the most common loss vector.

URL and bookmarks

Access exchanges/wallets only via saved bookmarks. On mobile, pin a home-screen shortcut. Check HTTPS and the second-level domain.

Address poisoning

Never copy addresses from transaction history. Use your saved address book. Verify first/last 4 characters and confirm on-device.

Never paste seed or grant remote access

No support representative will ask for it. Never install remote-control software for "help."

5.3+Phishing Drill — Spot the Fake

Question 1 of 5: Which domain is legitimate?

5.4Approvals/allowances (DeFi)

A token approval lets a contract spend your tokens — often with unlimited allowance.

Risk

If a contract is compromised or malicious, funds can be drained without further prompts.

Revoke practice

Periodically review approvals with a service like revoke.tools and revoke unused/unlimited ones.

Best practices

Approve minimal amounts, use a separate wallet for farming, isolate activities by role.

5.4+Approvals Demo (Mock)

This is a mock demo — no real blockchain calls. Practice revoking unlimited approvals.

TokenSpenderAllowanceDateAction
USDCFarmContractV1Unlimited2024-09-10
ETHSwapRouter5002024-10-02
WBTCLendingPoolUnlimited2024-08-15
DAIUnknownContractUnlimited2024-11-01

5.5Hardware wallets and basic multisig

For meaningful sums, hardware is the norm. Multisig is the next level.

Verify on-device

Always confirm the address on your hardware wallet screen before signing.

Trust screen only

Malware can spoof addresses on your computer — never rely solely on what you see on screen.

When to move to hardware

If losing it would hurt financially or emotionally, it's time. Hardware reduces malware/keystroke risks.

Verify address on-device

Confirm receiving/sending addresses on the hardware screen, not just the computer/phone.

Basic multisig

2-of-3 for teams/families reduces single-point failure, but requires disciplined key storage and recovery planning.

Compliance Notice: Educational only, not financial advice. Never share seed/passwords/codes. We never request or store your secrets. Use third-party services at your own risk. Practice with small amounts or test networks.

5.6Do it now — action cards

Actions completed0 / 5
Enable TOTP 2FA
10–15 min
  1. 1Set up TOTP in your exchange profile
  2. 2Write down backup codes offline
  3. 3Turn off SMS 2FA
Turn on withdrawal allowlist
10 min
  1. 1Add 1–2 of your addresses
  2. 2Enable delay for new addresses
Create an offline seed backup
15 min
  1. 1Write the seed clearly on paper
  2. 2Make a second copy
  3. 3Store copies in separate safe locations
  4. 4Verify readability
Review and revoke approvals
10 min
  1. 1Open an approvals checker (e.g., revoke.tools)
  2. 2Scan your tokens
  3. 3Revoke unnecessary or unlimited approvals
  4. 4First-timers: use testnets for practice
Verify address on-device
2 min
  1. 1Match first/last 4 chars on the device screen before sending

5.7Security Playbook

This is your personal security protocol. Do not enter any secrets here. Generated locally, not sent anywhere.

Playbook Preview

=== SECURITY PLAYBOOK ===

Generated locally. No secrets stored.

--- EXCHANGE ---
Password manager: ___
TOTP enabled: ___
TOTP setup date: ___
Allowlist enabled: ___
Allowlist setup date: ___
Anti-phishing code set: ___

--- SELF-CUSTODY ---
Seed backup method: ___
Backup locations (general): ___
Passphrase used: ___
Passphrase maintenance plan: ___

--- PHISHING HYGIENE ---
Bookmarks list: ___
URL check rule: ___

--- DEFI ---
Revoke cadence: ___
Wallet roles: ___

--- HARDWARE / MULTISIG ---
Threshold to use hardware: ___
Address verification rule: ___
Multisig setup (if any): ___

--- INCIDENT PLAN ---
Steps on suspected compromise: ___
Steps on device loss: ___

5.8Security Quiz

Mini-Quiz

Test your understanding with 8 questions. Pass with 6/8 correct.

Resources

Non-affiliated; verify domains yourself.

  • Official help centers of your exchange/wallet (security sections)
  • Authenticator apps docs (Aegis, Authy, 1Password/Bitwarden)
  • Approvals checkers (e.g., revoke.tools) — use at your own risk
  • Block explorers (official domains)
Compliance Notice

Educational only, not financial advice. Never share seed/passwords/codes. We never request or store your secrets. Use third-party services at your own risk. Practice with small amounts or test networks.