25
votes
Accepted
How can I manually (on paper) calculate a Bitcoin public key from a private key?
I've spent a fair bit of time thinking about this and can provide a fairly comprehensive answer about the state of the art. But unfortunately the TL;DR is that we don't know how to do this (yet) in ...
- 721
17
votes
Should I share my seed phrase to earn airdrop tokens?
No, it is not safe. Never share your 12 word phrase. It is a backup of your private key and allows people to spend your money. They only need your public key or Bitcoin address to give you money, not ...
- 432
11
votes
Accepted
BIP32 recommends a 256 bit seed. Why do most Bitcoin wallets only use a 128 bit seed?
The reasons for the 3 numbers:
Bitcoin uses 256-bit ECDSA signatures. These require in the order of 2128 steps to find a private key from the public key is known. This is Bitcoin's security level: we ...
- 109k
10
votes
Alert Key Compromised, upgrade required
The network wide Alert system is being retired. No Bitcoins are at risk and this warning may be safely ignored. Upgrade to the newest version of your wallet software to no longer see the alert.
Read ...
- 266
6
votes
Accepted
Is It Possible to Prove Ownership of Public Key Hash without Public Key?
The simple answer is no.
A hashing algorithm is ment to be a one-way function. If it is possible to recreate the public key from the hash, this means that the hashing algorithm is broken.
However ...
- 546
6
votes
Sugar Daddy Bitcoin
It is a scam.
He wants to get you comfortable with a process he can exploit later by sending you larger sums and getting you to pay an accomplice most. Maybe in a week or a month he will say he wants ...
- 28.4k
5
votes
Accepted
I'm new to Bitcoin, how do I keep my bitcoins secure?
Use a desktop or mobile wallet (Electrum or Mycelium) to spend bitcoins (be sure to write down your recovery seed and store it like a paper wallet). To receive and store them, use offline paper ...
- 281
5
votes
I'm new to Bitcoin, how do I keep my bitcoins secure?
Wallet
The wallet holds the most valuable component of the bitcoin network, your private key.
When you go to Bitcoin.org, there are several choices.
A HD wallet (Hierarchical Deterministic) is more ...
5
votes
What did I do wrong that caused me to lose bitcoin?
1) If you generate your paper wallet on your computer, you have to fully trust your computer
2) If you use a website for generating your paper wallet, a) you need to trust that website (hopefully its ...
- 6,072
5
votes
Relationship of Bitcoin address and Public Key
Addresses are textually encoded public key hashes, which means that somebody in possession of only the address cannot read the public key - but eventually the public key must be revealed in order to ...
- 3,349
5
votes
What stops a wallet from stealing bitcoins?
As @Prayank mentioned before: Nothing. As Ken Thompson said: "you can't trust code that you did not totally create yourself".
If you are paranoid, it's better that you use cold wallets and ...
- 151
5
votes
How do wallets work?
Does it create a public key based of private?
Yes, a cryptographic routine exists that computes the public key from the private key.
maybe on the wallet.dat file?
All modern wallet software ...
- 109k
5
votes
Accepted
Someon offered me btc mine trough his mining device
Yes, it's a scam. Don't send them anything.
- 2,078
5
votes
Accepted
How is Blockstream Jade's PIN secure?
there is a client secret key on the jade, and the client secret + the PIN are used in the key exchange. if the key exchange authentication phase fails too many times (wrong PIN) then the server secret ...
- 66
4
votes
What is the most secure operating system that I can use to store bitcoins without having to fear a hacker stealing them?
The most secure operating system is no operating system. As Pieter mentioned in the comments, dedicated hardware wallets prevent private keys from leaking out of the secure hardware enclave, and ...
- 1,041
4
votes
Accepted
Should I put my bitcoin wallet on an encrypted disk or not?
This only helps when someone malicious has physical access to you hard drive while your computer is not operational (shut down, account logged out, screen locked, etc.). When your operating system is ...
- 3,234
4
votes
Accepted
My blockchain.info wallet was hacked. How can I create a double send to foil the attacker?
So some background as to what happened here. I wanted to claim my bitcoin diamond air drop. I googled and this video came up first.
The video played this weird music which I think was hypnotic in ...
- 101
4
votes
Accepted
How does crypto exchange secure private keys?
Exchanges typically have a split storage setup. They have a hot wallet and a cold wallet. The hot wallet holds private keys on an online server that can quickly send and receive Bitcoin for when ...
- 72.1k
4
votes
Accepted
How can I safely store and trade Bitcoin and other crypto currencies?
There are several ways to store cryptocurrencies, so let's break them down by use-case and safety-level.
Exchanges
There are, broadly speaking, two types of exchanges. Centralized exchanges, such as ...
- 17.3k
4
votes
Accepted
Best OS for cold storage
Use TAILS Linux. From the website:
Tails is a live operating system that you can start on almost any computer from a USB stick or a DVD.
It aims at preserving your privacy and anonymity, and ...
- 10.2k
4
votes
Accepted
What can you do with the private key?
Anyone who knows the private key will have full access and control of any coins stored at the corresponding address.
When you put a password on a wallet or login account, that password is only for ...
- 18.4k
4
votes
What can you do with the private key?
What if a person has your private key?
Then they have independent control over all the unspent Bitcoins associated with that private key. Once they have the private key there is nothing you can do ...
- 28.4k
4
votes
Who store seed phrases data
who store the private key adresses of these seed phrases,
The private-keys are generated from the seed-phrase by a mathematical function. There is no need to store a list of seed-phrases and ...
- 28.4k
4
votes
Blockstream Green Wallet Security
Part of the design is that compromise of their service is a little bit pointless. They can not sign transactions spending your money to begin with, as the transactions also need a signature from your ...
- 15.5k
4
votes
Is the public address for Tesla's wallet known?
No, it's not known, and information like that generally won't be publicly released. Bitcoin addresses aren't generally publicly associated with the real-life identities of their owners.
I would expect ...
- 2,078
4
votes
Are Satoshi's satoshis less secure than they should be?
Most early transactions including rewards for early blocks go to P2PK outputs and we don't know who owns them, Satoshi or others. In these output scripts (unlike the common ones today) we use the ...
- 1,438
4
votes
Accepted
Why is it bad to split up a wallet seed redundantly?
Your analysis is correct. The weakness in this scheme is that if one location is compromised, only 80 bits of security are left. But 80 bits is sufficient for practical purposes and would likely take ...
- 51.7k
4
votes
Accepted
Muun Wallet - All Funds Stored On-Chain?
At the time of writing this, Muun does indeed store all balance on-chain. It does not open any Lightning channels and instead uses submarine swaps for Lightning payments, which means it has to make an ...
- 10.4k
4
votes
Accepted
Bitcoin Core wallet: two people with the same passphrase?
The passphrase for the Bitcoin Core wallet is just a passphrase for encrypting the wallet file. It is not a seed phrase from which the key material itself is derived. The keys are derived from a ...
- 109k
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