Bitcoin Stack Exchange
Bitcoin Stack Exchange

Questions tagged [attack]

Relates to attempts to harm the Bitcoin network. In cryptography, an attack is a method/technique to break the code. Bitcoin also has to deal with other types of attack, such as double spends and denial of service.

Relates to attempts to harm the Bitcoin network. In cryptography, an attack is a method/technique to break the code. Bitcoin also has to deal with other types of attack, such as double spends and denial of service.

202 questions
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Attack the network by temporarily adding hash power?

Could a malicious actor (e.g. government) attack the network by introducing significant compute power into the network, and once the difficulty grows very high, withdraw all resources from the network. This could dramatically increase the time it…
levi
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Current block vs whole block chain attack

If an evil computer network wanted to attack Bitcoin, would they need to have more computing power than the present Bitcoin network and then attack a current block, or would they need even more to go back and recalculate all the checksums in the…
shoeless joe
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Name of attack where you pay a high fee to block others

Is there a name for an attack where someone with a lot of capital makes loads of transactions with a high fee, just to prevent other transactions from taking place? This seems like a moderately cheap way of preventing 99% of all transactions. Is…
M Johnson
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Probabilty of a Race Attack in time t with hashing power q

I read the original Satoshi's paper on bitcoin as well as Rosenfeld's paper on "Analysis of hashrate-based double-spending". However, they don't answer my question, which is as follows. Let's assume attacker has q hash power (less or more than 50%)…
Maciej Żurad
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2 answers

Attack on bitcoin network with modified client?

Scenario: Mallory, Alice and Bob found block on their farm. They disconnect from internet, simulating split and change all of nodes in their segment to malicious. Malicious nodes decrease complication of block founding, and dramatically outrace…
trankvilezator
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Probability an honest node finds the next block vs. probability the attacker finds the next block

I am trying to understand Satoshi's paper [1]. On page 6 of the paper, he calculates the probability that someone can attack the blockchain from z blocks behind. He begins by defining: My question: The mining of a block i.e., solving the hash…
morpheus
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attack bitcoin through writing data directly into output's scriptPubKeys

In this post, Steve Ellis wrote : "[...]Writing data directly into a output's scriptPubKey is not prunable[...]where as non-prunable outputs will forever create bloat and slowdown the set traversal(e.g. during block verification).[...] Wouldn't…
I'll be respawned
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Is this man-in-the-middle double-spending attack against Bitcoin viable?

There is an almost trivial double-spending attack against Bitcoin if an attacker has a MITM (man-in-the-middle) attack against a victim: the attacker prevents all blocks from being seen, and replaces them with their own. The argument against this…
BlueRaja - Danny Pflughoeft
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What stops this style of attack on the Bitcoin network?

I was having a look at the genesis block of Bitcoin earlier and noticed the difficulty was set to 1. I guess this was originally designed so just Satoshi's computer mining at this difficulty would produce 10 minute blocks. However, if I put my…
N B
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What is to stop a malicious attacker only mining 1 transaction per block?

Even without 51% of the mining power, if you have say 5% of mining power and you deliberately only mine 1 transaction in your block aren't you going to create a traffic jam of transactions and effectively DDOS the network? (And the 1 transaction…
AndyM
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What prevents an attacker from doing DDOS on bitcoin network by sending billions of transaction to himself?

I know that transacion fees on low-priority transactions adds additional cost, but what if an attacker uses a lot of 0.100001 BTC transactions, so he doesn't have to pay the fee, because transactions are greater than 0.01 btc, and wouldn't be…
user3362334
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Attack in bitcoin network

I am new to blockchain and quite curious about some attack in bitcoin network. So, assume there is already an existing block which has content A and address B. Let's say if an attacker changes the block's content to A' and changes the address to B'.…
Mirage
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Revealing chain earlier when private attack

Private attack is to violate the safety of a block B by creating another chain of length equal to or longer than the longest chain containing B, after B has been confirmed. As in my reference If the adversary reveals its chain too early, i.e.…
Paul Yu
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Convert raw values to Int

how do I convert the given raw values in RSZ and Hash to integer? Is there an online convertor or a script I can use?
Roy Nahar
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