Bitcoin and malicious hackers

[FriendlyHacker]

If bitcoin money can be generated by robots, odds are not very good this new currency will survive. A malicious hacker could effectively crash the market with a large enough botnet. It also incentivizes problem solvers to spend their time going outside the law and causing harm, instead of helping people with new technologies that make life easier.

 

I don't know much anything about bitcoin, but read this post and tell me if what I said above is possible: http://www.reddit.com/r/IAmA/comments/sq7cy/iama_a_malware_coder_and_botnet_operator_ama/

[Ancient Mariner]

From the Bitcoin whitepaper (which you can find here: http://bitcoin.org/bitcoin.pdf)

 

The system is secure as long as honest nodes collectively control more CPU power than any cooperating group of attacker nodes.

 

If a greedy attacker is able to assemble more CPU power than all the honest nodes, he would have to choose between using it to defraud people by stealing back his payments, or using it to generate new coins. He ought to find it more profitable to play by the rules, such rules that favour him with more new coins than everyone else combined, than to undermine the system and the validity of his own wealth.

 

[FriendlyHacker]

"Some people just want to see the world burn" The Joker

 

Specially if bitcoin undermines their power (banks).

 

It's not unrealistic at all to have a larger botnet than honest nodes, we already have that, it's called Windows.

[TheRobin]

it would really help a ton, that, if you want to inform people about these things, that you'd maybe include a link or two where the argument is made. Simply saying windows is a botnet and leave it at that is not really helpful, even if it's true.

[Wesley]

Currently, bitcoin is out of reach of all of the largest super computers put together as far as CPU power. It would require a massive mobilization of resources that would cost more than bitcoin is worth in order to stop it.

 

As bitcoin increases in value, more honest nodes come into creation and more people would notice if someone was amassing such power and could find a way to safeguard against it before it is completed.

 

It is somewhat the nature of the system that it will always cost much more to stop it than it is worth, which is the entire point of cryptography.

[Ancient Mariner]

"Some people just want to see the world burn" The Joker

 

Specially if bitcoin undermines their power (banks).

 

It's not unrealistic at all to have a larger botnet than honest nodes, we already have that, it's called Windows.

 

If the attacker botnet is utilized to generate new bitcoins then nothing is undermined. Inflation will not occur since the Bitcoin protocol is designed in such a way that new bitcoins are created at a fixed rate.

 

The biggest risk is defrauding people through a double spend attack. And I guess if someone really wanted to bring the system down they would try to append blocks in the chain that contain completely arbitrary and random transactions. When this is discovered I would imagine the block chain could be just rolled back to the previous uncompromised block. I believe something similar happened some time ago when a large account was hacked and performed random valid transactions. 

  

I would imagine that hackers are on the side of bitcoin (and against the establishment) and I don't know how bankers and/or governments can infiltrate as honest nodes without creating malware. However, I don't know too much about the hackers community or if hackers in the payroll of governments are effective enough to it.

 

Also, I don't know how stable the number of computers in a botnet is. I would imagine the computers with large processing power belong to gamers which would notice a decrease in performance and remove malware soon after.

[TheRobin]

 people would notice if someone was amassing such power and could find a way to safeguard against it before it is completed.

 

As far as it's been explained to me by someone who's way more competent at the technical stuff than I ever will, this is not true. IF someone wants to secretely create a fraudulent blockchain, all they need is the hashpower but it doesn't need to be online, so no one would notice it. (I know too little about botnets to say how realitstic that is from that standpoint though). Unless you mean with "amassing" that they buy the necessary hardware openly for everyone to see, then I guess that is visible unless it's some weird black market ASIC stuff :)Also as I've been told, thanks to the network not being synchronsied the attacker would also only need 45%, not taht that's all too relevant, just thought I throw it out there, as I found it an  interesting tidbit of info

[ribuck]

As far as it's been explained to me by someone who's way more competent at the technical stuff than I ever will ... IF someone wants to secretely create a fraudulent blockchain, all they need is the hashpower but it doesn't need to be online, so no one would notice it. (I know too little about botnets to say how realitstic that is from that standpoint though).

 

The guy who explained it to you is correct. However, the standard Bitcoin client hardcodes some checkpoints which mean that an offline attack cannot start any earlier than the latest checkpoint. If an offline attacker suddenly released a longer block chain, it would be possible "in extremis" for Bitcoin users to thwart the attack by upgrading their Bitcoin client to one with a later checkpoint on the "good" blockchain. This would be messy, but would avoid the attack succeeding.

 

Most of the hashpower now comes from dedicated ASIC hashing chips, whose hashing power is so high an attack by a botnet of regular PCs is no longer feasible. It would be necessary for the attacker to be hashing with their own ASICs.

[TheRobin]

oh, okay, thanks for the clarifictaion