Quote from: The Pharmacist on December 23, 2021, 04:32:46 PM

I'm unbelievably ignorant of computer science and programming, so I don't know what those attack vectors are for PoS coins (and I haven't read anything about that topic). I don't want to go off-topic, but I'm curious as to what those are and if they've ever compromised a PoS coin before. I've been a fan of them for a while now--and yeah, you can call me stupid for that if you like--and I haven't heard of a PoS coin that's been hacked or attacked or what have you.

The most recent thing I could think of is the paper by cryptography experts from Stanford University on 3 attack vectors on ETH PoS: https://arxiv.org/pdf/2110.10086.pdf
Cost of such attacks is negligible compared to cost of attacking even a low hashrate PoW.

Generally speaking we can name some of the serious PoS attack vectors:
- The adversary who controls a large amount of PoS coin can have a strong control over that network. For example the premined altcoins or cheap coins that could be bought with little amount of money. It is like PoW 51% attack but it doesn't necessarily need 51% of the supply.
- Long range attack called Stake Bleeding where the adversary can build an alternative chain without publishing it until it is long and the adversary has a huge stake in that chain then publishes it essentially replacing the entire honest blockchain with very little cost: https://eprint.iacr.org/2018/248.pdf
- Another long range attack called "Posterior Corruption" or "“costless simulation" which is when an old stake holder who has sold their stake perform a history-rewrite attack: https://eprint.iacr.org/2016/919.pdf This could also happen if someone bought the old keys used for staking

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The whole "getting paid for having money" thing isn't necessarily a design flaw, nor is it a new concept. Investors who own dividend-paying stocks get paid for holding their stock, and it's a perfect example of passive income.

Then PoS coins should not be called cryptocurrencies anymore. Lets refer to them as high risk cryptoinvestments.

Another fundamental flaw in this economical design IMO is that those who are securing the network in Proof of Stake can abandon that chain in an instant and move to another chain. All they have to do is to dump their coins and convert them to another PoS coin.
This is not as easy in PoW because the miners that are securing the PoW chain can not easily dump their ASICs and buy new ones to mine an alternative algorithm. Even the reward you get in a PoW algorithm can not be dumped right away, coinbase outputs have to "mature" for 100 blocks before they can be spent.