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Questions tagged [security]

This tag should be used for questions regarding security issues with the design or implementation of Bitcoin and related cryptocurrencies.

8
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2answers
21k views

Creating a fake transaction

AttackerAlice has a BTC Wallet with 0 BTC. AccompliceBob has a BTC Wallet. Is it possible to transfer 100 BTC from AttackerAlice to AccompliceBob? Suppose a BadMiner accepted this as a valid ...
0
votes
1answer
14 views

Security of ChaChaPoly (IETF rfc7539) in the noise protocol framework of the Lightning Network

According to this paper ChaChaPoly is secure against chosen known plaintext attacks. I wonder however if that security assumption is weakened by a lot since messages sent on the transport layer of the ...
10
votes
1answer
2k views

Bitcoin automatically diverted to bech32 address

I sent bitcoin to an address starting 3Cn using Electrum but the blockchain viewers seem to show that it has gone to an address beginning bc1 as shown in the link below. Transaction Viewer How can ...
1
vote
2answers
41 views

Why was noise XK fundamental pattern chosen in the transport layer (BOLT 08) of the lightning network

I am currently reviewing the transport layer of the Lightning network protocol. It builds on top of the noise protocol framework handshake patterns. What I don't get: Why was the fundamental pattern ...
1
vote
1answer
91 views

Byzantine Fault Tolerance Threshold of Bitcoin: 1/2 or 1/3? (Edited)

According to this answer: https://bitcoin.stackexchange.com/a/58908/41513 a Byzantine Fault Tolerant (BFT) consensus threshold is 1/3. On the other hand, there is a common belief that Bitcoin network ...
3
votes
1answer
43 views

Why is the length of the transport messages on the lightning network encrypted?

From BOLT 08 we can see that every message is sent in the following way: 2 byte: length 16 byte: MAC [length] byte: Encrypted message 16 byte: MAC In reality these messages will be send over TCP/...
4
votes
1answer
38 views

Does MuSig have the same security as 2-2 multisig?

Disclaimer: This question is of theoretical importance to me trying to educate myself better on cryptographic principles and signature schemes. I don't intend to imply that in practice schnorr ...
0
votes
0answers
42 views

How may bitcoins hash algorithm be secured in the future from quantum computing brute forcing?

Other threads already answer very clearly that quantum comps could easily "break" /attack bitcoins chain. Now: Are there any ideas among the bitcoin devs circulating out there, how to save bitcoin ...
0
votes
2answers
39 views

If a bitcoin wallet service provider terminates a users account, what happens to the funds?

A friend of mine has/had a bitcoin wallet service provided by an online marketplace. Sounds like he had some kind of disagreement with the site administrators and they terminated his account. At that ...
0
votes
1answer
40 views

Permissioned or Permissionless blockchain? Which one is PoS more adapted for?

Since in proof-of-stake (PoS) there is no mining process, according to functionality of permissioned and permissionless blockchains, which type is PoS more adapted for? In the other words, is a PoS-...
0
votes
2answers
41 views

How secure is using TOR in Lightning Network?

In following paper (Link to the paper) we read: "combining Tor and Bitcoin creates an attack vector for the deterministic and stealthy man-in-the-middle attacks. A low-resource attacker can ...
0
votes
1answer
50 views

Does a HD Wallet log my IP when i do a transation?

Companies like BitPay and Electrum, can log my IP when i make a transation, right? If so, should i use a Web Wallet (plus VPN) for transactions?
5
votes
2answers
587 views

How to perform a double spend attack in websites that accept transactions with 0 confirmations?

To perform a Finney attack or a 51% attack I need to have lots of computational power, but in this case (a website that accepts transactions with 0 confirmations) it seems to me that I only need to ...
12
votes
5answers
3k views

How safe is a brain wallet?

Edit: The answer is that they are unsafe and have been attacked. Please don't use them! Brain wallets can be created with a (minimum 15 character) pass phrase at https://www.bitaddress.org There are ...
0
votes
1answer
210 views

Are DAG-based crypto currencies as secure as proof-of-work based blockchains?

A key feature of blockchain based cryptocurrencies is that they provide inherently secure systems that don't rely on third parties. The newer DAG-based cryptos like Byteball are being touted as ...
0
votes
2answers
7k views

Can I modify the source code of Bitcoin to generate addresses people have already used?

Each time you start bitcoin-qt.exe program will generate new random address But what happen if I modify source code and compile new version: instead of new random address I can hard code in source ...
2
votes
1answer
56 views

Does LN require an on-chain “emergency lane” to mitigate systemic risks?

According to LN social slides, a fee market (in other word: "congested mempool", to my understanding) is good. But, there's systemic risks around penalty mechanism, so some sort of on-chain scaling (...
1
vote
1answer
29 views

How could an LN node acquire inbound liquidity? Is there any systemic risk?

I once heard that LN could support dual-funded channels. It doesn't seem so complicated, but currently, I don't know any LN wallet which supports creating dual-funded channels. By the way, I'm also ...
0
votes
3answers
78 views

Is it smart to just create wallet and then delete it, writing down the address?

What are possible downsides of practice where I download a bitcoin wallet on my phone, write down the seed and the address, purge the app into nonexistence and continue my happy life, sharing my ...
13
votes
2answers
2k views

How do you derive the private key from two signatures that share the same k value?

I wrote my own ECDSA signature algorithm just for the purpose of creating unit tests. With it I created two signatures which went into transaction 56ec7ca7df..., sending from 1GXFXm3es.... These ...
20
votes
3answers
10k views

Is Each Bitcoin Address Unique?

I am wondering whether each bitcoin address is unique. I would assume yes. Then how is this enforced (distributed address generation)? As I understand it each time, an address is generated a new key-...
7
votes
2answers
2k views

Is a bitcoin address collision possible if generating 90 million addresses every 4 hours?

I am running a test to see if I can obtain a successful bitcoin address collision after generating billions of addresses. I am not entirely sure how I would check them yet. Basically I have an extra ...
6
votes
2answers
188 views

Can a full node provide a bogus block bloomfilter to a Neutrino node?

When a thin client using BIP157/BIP158 (Neutrino) requests the block filter for the latest block, would it be possible for the full node serving this request to attack the Neutrino node by providing a ...
0
votes
1answer
58 views

LND Security best practices? Disaster recovery?

Can anyone share a knowledge how to _ secure LND node _ backup node with all Channels I think only a seed will not be sufficient. What is your plan B in case of disaster? How to do an Emergency ...
0
votes
2answers
41 views

How could a lightweight wallet determine the validity of 0-conf transaction?

I found that a lot of people are interested about security of 0-confirmation payments. But, it seems that most discussions focused on double-spending (like broadcasting two or more conflicting-but-...
13
votes
1answer
1k views

What is the origin of insecure 64-bit nonces in signatures in the Bitcoin chain?

In Biased Nonce Sense: Lattice Attacks against Weak ECDSA Signatures in Cryptocurrencies Joachim Breitner and Nadia Heninger use a lattice based algorithm to recover private keys from signatures in ...
3
votes
2answers
1k views

I think my bitcoin wallet was hacked. What to do?

I opened bitcoin-qt after not mining for a couple months and found that I suddenly have no more bitcoins! And I see that there were 2 transactions that I did not authorize sending my coins to other ...
1
vote
1answer
44 views

Security of Bitcoin Wallet

I have a doubt on Bitcoin wallet. Suppose I have an online Bitcoin wallet. Now, someone breaks into my computer and steals my Bitcoin wallet. Fortunately I have a backup of my wallet on another ...
3
votes
2answers
353 views

What is it about a Trezor that means it can't be infected by malware?

The Trezor testimonials include that TREZOR ... cannot be infected by malware What is it about a Trezor that means it cannot be infected?
4
votes
1answer
157 views

Lightning Network: asymmetry in the information tracked by each participant?

In following paper, written by Christian Decker et al., there is a paragraph that is not clear to me. eltoo: A Simple Layer2 Protocol for Bitcoin "The central idea of Lightning is to invalidate ...
1
vote
1answer
46 views

Security implications of removing CHECKSIG in a test

If I conduct an htlc transaction on testnet that does not include OP_CHECKSIG will it still cost an attacker more than (say) $10 in processing power or storage to subvert my tests? Details: I'm ...
2
votes
1answer
108 views

Lightning network hub security?

Reading the whitepaper, I came across a point: nodes wishing to act as effective intermediaries, 'hubs' or not, need high availability and need to operate autonomously. This means they must have ...
1
vote
1answer
176 views

Who decides what the next, correct Nonce is?

As I understand finding the correct Nonce is the basis when hashing transactions for Proof of Work. How and where is this decided in the ecosystem what the next Nonce is? In my limited understanding ...
1
vote
2answers
111 views

Does my Electrum wallet become less secure if I keep generating seeds until I see one I like the look of?

Let's say I want to create a new electrum seed... I didn't like the initial seed words, since I want to remember them and these didn't look too appealing. Looking "too random" for my taste. When I ...
0
votes
1answer
2k views

Private key to mnemonic words, is it safe?

Is it safe to do the following? Suppose I do not want the HD wallet, but I do want the convenience of using mnemonic words to remember the private key. I know I can convert the private key's hex ...
0
votes
1answer
33 views

How Spectre tolerates spam transactions?

Spectre is a DAG based (directed acyclic graph) distributed ledger (a structure as an alternative to blockchain based distributed ledger). Is there any mechanism in Spectre to prevent sending spam ...
0
votes
2answers
25 views

Physical bitcoin vs. Paper wallet?

What is the main difference between a Physical bitcoin and Paper wallet ? And which one is more secure ? And why ?
1
vote
2answers
206 views

What are the drawbacks of using a web based wallet and how to overcome that?

Can anyone tell me why many prefer to use application when compared to web based wallets. What are the drawbacks of using a web based wallet and how to overcome that?
3
votes
4answers
337 views

Store Bitcoins offline

I have some bitcoins and ether at Blockchain.info and I am really scared of losing them. How do I best secure them? Right now I have a paper with the code to restore my wallet, but my coins are still ...
6
votes
1answer
1k views

Why is increasing block size in the Bitcoin network considered to decrease security?

I have been doing some research on the Bitcoin Cash hard fork and the main contention of increasing the block size appears to be the possibility of less security on the network. How does an increased ...
0
votes
1answer
77 views

Why are the inputs of Bitcoin transactions signed?

This is my understanding of what a transaction looks like: inputs: input0: txid: <funding tx0 TXID> outputID: <output ID of UTXO in the funding tx0> scriptSig: <...
0
votes
2answers
48 views

What Happened 12/30/17 Last Recieved Transaction into Bitcoin Core Wallet

I have found a different receiving address within my wallet that is not mine... at least I did not create it. It seems to me that all of my transactions are now going to this new address instead of ...
0
votes
1answer
48 views

How does using a Turing-complete programming language compromise the security of the network? [duplicate]

I have read many places that the decision for Ethereum to use a Turing-complete programming language sparked a lot of concerns over security. From my understanding, not using a Turing-complete ...
1
vote
2answers
955 views

Is it possible to bruteforce the seed?

Is it true that the "seed words" bruteforce more reliable for to get profit than searching of a "random number" for to open some profitable outputs? The last one is impossible due to math, but the ...
1
vote
1answer
48 views

Bitcoin Mixing? Is it even real?

I have been trying to find a "bitcoin mixing" service but it seems that ALL the "bitcoin mixing" sites I have looked at are scam. Does anybody know of any that are actually real and do what they say ...
2
votes
2answers
109 views

Exact definition of “Liveness” and “Safety” properties in a consensus?

Two main properties of a consensus are "Liveness" and "Safety". What are the exact and precised definition of "Liveness" and "Safety" properties in a consensus ? Are the following definitions ...
1
vote
0answers
42 views

Why Spectre has a “weak” liveness?

According to this article: (https://medium.com/@avivzohar/the-spectre-protocol-7dbbebb707b5) written by one of Spectre's author (Aviv Zohar), it is mentioned that Spectre has weak liveness. What is ...
11
votes
1answer
243 views

Schnorr's batch validation

In the recent BIP about Schnorr's standardization, Pieter Wuille presents an algorithm for batch validation. In my understanding the most heavy operation is the multiplication by a scalar: to make ...
2
votes
0answers
68 views

Sybil attack with IOTA?

IOTA is one of the DLTs uses DAG (Directed Acyclic Graph) as data structure. The solutions to attacks proposed by IOTA white paper seems unconvincing, in particular, in case of double-spending, it ...
3
votes
2answers
1k views

Make remote RPC connection to bitcoind server secure

I set up a bitcoind server on an Ubuntu server and I can remotely execute commands on the server. I am doing this with Java/RPC. To execute a command I need to provide a username and password. But I ...