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r/Bitcoin: 'Bitcoin wasn't broken; the random key generation was' explainer

reddit-bitcoin-not-broken-explainer

https://www.reddit.com/r/Bitcoin/comments/1vjf9jw/bitcoin_wasnt_broken_the_random_key_generation/

Latest reviewed change

source content difference between and

The thread gained a comment stating the reduced key search space is far larger than three billion.

seen +8 -0 full history below
 body:
 That’s why a TRNG is important
 
+comment: p3qdgjw
+parent: t1_p2o8c4q
+author: Quiet_Acanthisitta97
+created_utc: 1786744637
+edited: false

First lines only. The complete diff is in the timeline below.

Organisation
reddit
Evidence role
Community discussion
Published
not established
Source changes
2
Detected differences
2
Unreviewed
0
Copies held
3

Every check is recorded, including checks that found no text change. A detected edit is therefore bounded between two checks. The publisher's exact save time is not observable from this record. Last checked .

  1. source content difference between and Current source content +8 -0

    The thread gained a comment stating the reduced key search space is far larger than three billion.

    seen · Captured here 28,928 chars
    What changed from the previous capture 8 lines
     body:
     That’s why a TRNG is important
     
    +comment: p3qdgjw
    +parent: t1_p2o8c4q
    +author: Quiet_Acanthisitta97
    +created_utc: 1786744637
    +edited: false
    +body:
    +There is allot more than 3 billion man. It's more than there are atoms in the universe
    +
     more-stub: parent t1_p2o324k count <live-count>
    
    Extracted text as captured
    post: 1vjf9jw
    author: kisscardano
    created_utc: 1786246610
    title: Bitcoin wasn't broken. The random key generation was. The Coldcard lesson everyone should understand
    body:
    To explain the Coldcard disaster as simply as possible, imagine you have **3 billion grains of sand**, and one grain is marked.
    
    If I ask you to find the marked grain, you have to search through billions of grains. Pretty difficult.
    
    Now imagine I make a mistake and tell you that the marked grain is actually **somewhere among only a few hundred grains**.
    
    Suddenly, finding it is easy. You just check the few hundred grains one by one.
    
    That is basically what happened with the Coldcard vulnerability.
    
    A Bitcoin private key is normally chosen from an unimaginably huge number of possibilities. The whole point is that nobody can realistically search through them all.
    
    But because of a bug, some Coldcard devices could generate keys from a **much smaller and predictable set of possibilities** than they should have.
    
    So an attacker didn't have to search through the entire universe of possible Bitcoin keys. They could concentrate on this much smaller set and test the possibilities against the blockchain.
    
    With a powerful computer, they could eventually find the private key and steal the Bitcoin.
    
    So the simple version is:
    
    **Billions of grains = practically impossible to search.**  
    **A few hundred grains = easy to search.**
    
    The security wasn't broken because Bitcoin's cryptography was cracked. The problem was that the key was generated from a much smaller pool of possibilities than it should have been.
    
    comment: p2l0bu1
    parent: t3_1vjf9jw
    author: Wrong-Contest-9617
    created_utc: 1786247107
    edited: false
    body:
    Yeah but this proves that holding crypto is very risky for the majority of the population 
    
    comment: p2l0ptb
    parent: t1_p2l0bu1

    Excerpt only. The complete copy is held offline and backs quotations on this site. The original publication remains the canonical public source.

  2. source content difference between and source content +0 -12

    A comment by TheRivieraKid22 urging readers to learn about bank deposit insurance and avoid winging it was removed from the thread.

    seen · Captured here 28,731 chars
    What changed from the previous capture 12 lines
     You have a point, I guess when I say it I actually mean “don’t invest \[in any one thing\] what you can’t afford to lose.” Which is just diversification.
     
     Out of curiosity I did some googling. The original saying is actually “you shouldn’t speculate except with money you can afford to lose” and it comes from a 20th century economist. So you are right it was meant to refer to specifically high risk investments.
    -
    -comment: p2lsqpo
    -parent: t1_p2l2iys
    -author: TheRivieraKid22
    -created_utc: 1786260271
    -edited: false
    -body:
    -You should defiantly read up on your bank too 
    -
    -like what happens if the bank goes under - how much of your money is insured and will be returned. 
    -
    -winging it in life is how shit goes wrong regardless of the industry
     
     comment: p2lw05a
     parent: t3_1vjf9jw
    
    Extracted text as captured
    post: 1vjf9jw
    author: kisscardano
    created_utc: 1786246610
    title: Bitcoin wasn't broken. The random key generation was. The Coldcard lesson everyone should understand
    body:
    To explain the Coldcard disaster as simply as possible, imagine you have **3 billion grains of sand**, and one grain is marked.
    
    If I ask you to find the marked grain, you have to search through billions of grains. Pretty difficult.
    
    Now imagine I make a mistake and tell you that the marked grain is actually **somewhere among only a few hundred grains**.
    
    Suddenly, finding it is easy. You just check the few hundred grains one by one.
    
    That is basically what happened with the Coldcard vulnerability.
    
    A Bitcoin private key is normally chosen from an unimaginably huge number of possibilities. The whole point is that nobody can realistically search through them all.
    
    But because of a bug, some Coldcard devices could generate keys from a **much smaller and predictable set of possibilities** than they should have.
    
    So an attacker didn't have to search through the entire universe of possible Bitcoin keys. They could concentrate on this much smaller set and test the possibilities against the blockchain.
    
    With a powerful computer, they could eventually find the private key and steal the Bitcoin.
    
    So the simple version is:
    
    **Billions of grains = practically impossible to search.**  
    **A few hundred grains = easy to search.**
    
    The security wasn't broken because Bitcoin's cryptography was cracked. The problem was that the key was generated from a much smaller pool of possibilities than it should have been.
    
    comment: p2l0bu1
    parent: t3_1vjf9jw
    author: Wrong-Contest-9617
    created_utc: 1786247107
    edited: false
    body:
    Yeah but this proves that holding crypto is very risky for the majority of the population 
    
    comment: p2l0ptb
    parent: t1_p2l0bu1

    Excerpt only. The complete copy is held offline and backs quotations on this site. The original publication remains the canonical public source.

  3. Earliest copy held
    seen · Captured here 29,054 chars
    Extracted text as captured
    post: 1vjf9jw
    author: kisscardano
    created_utc: 1786246610
    title: Bitcoin wasn't broken. The random key generation was. The Coldcard lesson everyone should understand
    body:
    To explain the Coldcard disaster as simply as possible, imagine you have **3 billion grains of sand**, and one grain is marked.
    
    If I ask you to find the marked grain, you have to search through billions of grains. Pretty difficult.
    
    Now imagine I make a mistake and tell you that the marked grain is actually **somewhere among only a few hundred grains**.
    
    Suddenly, finding it is easy. You just check the few hundred grains one by one.
    
    That is basically what happened with the Coldcard vulnerability.
    
    A Bitcoin private key is normally chosen from an unimaginably huge number of possibilities. The whole point is that nobody can realistically search through them all.
    
    But because of a bug, some Coldcard devices could generate keys from a **much smaller and predictable set of possibilities** than they should have.
    
    So an attacker didn't have to search through the entire universe of possible Bitcoin keys. They could concentrate on this much smaller set and test the possibilities against the blockchain.
    
    With a powerful computer, they could eventually find the private key and steal the Bitcoin.
    
    So the simple version is:
    
    **Billions of grains = practically impossible to search.**  
    **A few hundred grains = easy to search.**
    
    The security wasn't broken because Bitcoin's cryptography was cracked. The problem was that the key was generated from a much smaller pool of possibilities than it should have been.
    
    comment: p2l0bu1
    parent: t3_1vjf9jw
    author: Wrong-Contest-9617
    created_utc: 1786247107
    edited: false
    body:
    Yeah but this proves that holding crypto is very risky for the majority of the population 
    
    comment: p2l0ptb
    parent: t1_p2l0bu1

    Excerpt only. The complete copy is held offline and backs quotations on this site. The original publication remains the canonical public source.

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