<p>Personally I would never let anyone know I had any knowledge of crypto at all.</p>
<p>But yes the &quot;deniability wallet&quot; against the $5 wrench attack is one aspect.</p>
<p>The BIP39 passphrase should be secure, not anything you choose yourself, it can be as long and complex as you like, even another whole mnemonic or Diceware sequence.</p>
<p>It creates a whole new Account-Wallet seed.</p>
<p>Should be backed up to a separate cryptosteel in a different location from your main mnemonic.</p>

CC BY-SA 4.0
2022-03-22T01:36:05.000Z
2022-03-22T01:36:05.000Z
HansBKK
<p>I understand that the 25th word is to protect your assets when your 24 seed phrases are compromised. But I have some questions:</p>
<ol>
<li><p>If I use a simple word as the 25th word, it will be easily brute force attacked. So is it useless unless I set the 25th word very long (20+ chars) and memorize it using my brain?</p>
</li>
<li><p>Or the situation is like this. The address with only 24 words has a small amount of crypto that you can lose. When someone gets your seed phrases, they think those are all your assets and did not realize you hide most of your crypto in the address protected by your passphrase. In this case, does it mean that I should not let anyone know I have a hidden wallet with 24+1 words?</p>
</li>
</ol>

<private-key><attack><passphrase><safety>
What is the main purpose of the idea PASSPHRASE (25th word)?
Hinoon
# What is the main purpose of the idea PASSPHRASE (25th word)?

(Asked by: username_0 on 2022-03-21)

I understand that the 25th word is to protect your assets when your 24 seed phrases are compromised. But I have some questions:

1. If I use a simple word as the 25th word, it will be easily brute force attacked. So is it useless unless I set the 25th word very long (20+ chars) and memorize it using my brain?
2. Or the situation is like this. The address with only 24 words has a small amount of crypto that you can lose. When someone gets your seed phrases, they think those are all your assets and did not realize you hide most of your crypto in the address protected by your passphrase. In this case, does it mean that I should not let anyone know I have a hidden wallet with 24+1 words?

**Tags:** private-key, attack, passphrase, safety


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## 1 answers

### Answer by username_1 on 2022-03-22. Score: 2

Personally I would never let anyone know I had any knowledge of crypto at all.

But yes the "deniability wallet" against the $5 wrench attack is one aspect.

The BIP39 passphrase should be secure, not anything you choose yourself, it can be as long and complex as you like, even another whole mnemonic or Diceware sequence.

It creates a whole new Account-Wallet seed.

Should be backed up to a separate cryptosteel in a different location from your main mnemonic.


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