Would someone be able to explain this to me like I'm Alice or Bob?  ELIAB for short.

Another day, another drop.
Still below 2017 high when we consider inflation.

All is hunky dory with the economy apparently. Nothing to worry about. House prices are in fact up according to the lamestream UK media. (Thought there was 10% inflation? No mention of that, why would there be)

But sure, I'm the one being negative.

ThInGs ArE aBsOlUtElY fInE.

Ouch.

That's not a source to what you're claiming. This is speculating that in the future quantum computers could crack private keys, this is also nothing new.


So quantum computers could, theoretically, crack private keys in the near future. You said they can, but there is no evidence of this, only theory.


You're also confusing the two vulnerabilities here, considerably.

One is based on nonce reuse, that out of 424m public addresses, only managed to crack 773 addresses (less than 0.0002% of all addresses).  The idea with quantum computers has nothing to do with nonce reuse, but brute forcing SHA256 private keys (as far as I understand). If successful, that would theoretically mean 100% of addresses are at risk, as opposed to 0.0002%, and a soft fork would be needed.

So to say quantum computing isn't needed anymore to crack a private keys, is clearly complete nonsense. The point with the 773 addresses hacked is that the damage has more or less already been done (mostly years ago), with the exception of maybe around 50 addresses per year getting hacked, from people not using secure software or safe practices predominantly.

So for example, all wallets with unspent outputs - or even just 1 output, as referenced attack requires 2+ outputs minimum, but realistically 4+ - currently have no vulnerabilities.

I will try... from how I would picture it....

Alice is on a treasure hunt, and Bob tells Alice that the Treasure is located 500KM from the Empire State Building. Alice could draw a circle from the ESB with a 500KM radius and knows the treasure lays in that circumference. It will take a while, but eventually she will find it (brute force). However, she may ask for more clues, but each time Bob tells her where to find the treasure, he also hides it in a new location. So this time it is 600KM from Statue Of Liberty, again she will have to draw a circle with a  600KM radius from SOL and knows the treasure lays within that circumference. Again She will find it eventually....

Now lets say Bob, was lazy, and didn't want to re-bury the treasure, so when Alice asked for another clue, Instead of moving the treasure, Bob leaves it where it is and tells Alice that is is now 400KM from Liberty Bell. Using those two clues, She can now plot the two circles and where they intersect, two points, the treasure will be at one of the two points. Now imagine she asked for a third clue, assuming Bob is using the same spot he hid the treasure, the third clue will allow Alice to triangulate the location, where all three circles intersect is where the treasure is located.

That's pretty much what they did, they assumed people wouldn't "re-bury the treasure", each time they signed a transaction, and by scanning the blockchain database they were able to identify wallets that did reuse their nouce and using that information and mathematical equations. They were to derive the private key...

Fun fact: If I hid a grain of sand somewhere on earth, you would have more chances of finding it, than brute forcing a 256bit key....

EDIT: Grammar, too early in the morning!