Module 1 · How attacks actually start Lesson 2 of 15
Passwords, MFA and why length beats symbols
A long passphrase beats a short complex password, and reusing a password across sites is what turns one leaked database into ten compromised accounts.
The concept
Length beats complexity. A four-word passphrase of twenty-odd characters is far harder to crack than eight characters with a symbol and a capital — and it is easier to remember. Attackers do not guess; they try billions of combinations per second against stolen databases, and every extra character multiplies the work.
Never reuse a password between important accounts: one breach anywhere reveals that password, and attackers try it everywhere. Use a password manager so you only remember one, and turn on multi-factor authentication — the code on your phone after the password — on your mail and GitHub first. Mail is the skeleton key: password resets for everything else arrive there.
Length beats symbols: "purple-tiger-battery-lamp-7" > "P@ssw0rd!"
Use a password manager. Never reuse a password across sites.
Turn on MFA - an app or a hardware key, not SMS if you can avoid it.
Breached site? Change the password AND everywhere it was reused.Common mistakes
The mistakes are a system everybody in a household knows, a password written in plain text on the desk, and MFA codes read out on a call to somebody who asked for them. A support agent will never ask for your one-time code; whoever does is attacking you.
Worked example
Credential stuffing — trying leaked username and password pairs on other sites — works entirely because of reuse. Multi-factor authentication breaks it, which is why enabling it everywhere is the highest-value hour a beginner can spend.
Your practice task
Turn on MFA on your own email and two other accounts, and install a password manager. Use a long passphrase for the master.
Do this before moving on. Reading a solution teaches the shape of it; typing it teaches you.
Key takeaway
Length beats complexity. A four-word passphrase of twenty-odd characters is far harder to crack than eight characters with a symbol and a capital — and it is easier to remember.
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