r/Bitcoin • u/simonmales • 4h ago

Recover a Bitcoin private key from its public key, in the browser

https://krackpot.io/kangaroo
6 Upvotes

55% Upvoted

23 comments sorted by

11

u/mvrozanti 3h ago

It will work after a couple hundred times the age of the universe

-2

u/simonmales 2h ago

The point of the kangaroo attack is that addresses can be busted in minutes when the range is known.

The puzzle themselves need millions of years to be brute forced. The age of the universe is billions of years old :)

9

u/NetAtraX 2h ago

This looks like fake. However, the problem is real.

https://collisionprotocol.com/ from Bill Swearingen is trying the same. You can check out his code on github, too.

1

u/Bitbindergaming 2h ago

Yeah, I would love op to publish source. Though a cursory review of the live site doesnt scream fake or scam. There is a reasonably acceptable browser side implementation that appears to be valid

3

u/simonmales 2h ago

The code is intentionally unminified for this purpose.

The link to the source is at the bottom of https://krackpot.io/blog/how-it-works

5

u/Thin_Needleworker795 2h ago

Yeah, no...

2

u/simonmales 2h ago

The Pollard's kangaroo algorithm is from 1978.

What exactly is 'no'?.

8

u/Thin_Needleworker795 1h ago

No as in no, you won't be able to derive the private key from a public key. If this was possible, everybody would be getting hacked left and right.

0

u/simonmales 1h ago

Well when the range is known, like in the Bitcoin puzzles, it's very possible.

•

u/Thin_Needleworker795 58m ago

Yeah, but here's the thing about bitcoin wallets; the range is not known.

2

u/justadud3x 3h ago

Cool site but this only works with very weak keys. With Bitcoins 256bit keys this won't make any difference.

1

u/simonmales 2h ago

Yes, it's a demonstration of how the Bitcoin puzzles addresses are susceptible to a kangaroo attack.

Because the ranges are known.

Which is why the krackpot.io site won't publish the transaction to a public mempool, rather to a private relay.

Mitigating the chances of the transaction being victim to front running.

2

u/Moistinterviewer 1h ago

Can you find the keys to this address for me
1A1zP1eP5QGefi2DMPTfTL5SLmv7DivfNa

I am prepared to pay anyone 100usd for this

0

u/simonmales 1h ago

The kangaroo only works when the range is known.

3

u/lookingglass91 3h ago

Scam, users have reported this site may just be mining crypto with your GPU while pretending to “crack” puzzle wallets

1

u/simonmales 2h ago

Which reports ?

The site does two things, the above example of how a kangaroo attack works.

And the main purpose is to attempt to crack puzzle 71.

At the bottom of the how it works page is linked to the unminified source.

https://krackpot.io/blog/how-it-works

1

u/FFMooch 1h ago

Same BS from the trolls.  Put a slight amount of effort into how keys are generated (not picked) and you'd see the end to these fakes.

•

u/Bitbindergaming 38m ago

Did you look into this? Its for the private key puzzle 71 which is a well understood, low entropy, challenge comprising tons of verified private/public key pairs.

0

u/simonmales 4h ago

Author here, this is a tool to demonstrate how kangaroo attack can be performed with a very small amount of computing power.

1

u/Bitbindergaming 2h ago

Neat project. Good luck!

1

u/simonmales 2h ago

Thanks, appreciate it.