Popular blockchain game Axie Infinity was hacked and 600 Million US dollars was taken of Ethereum (the second largest cryptocurrency) and stable coins.  The hacker was able to hack via network validator nodes.  It is reported that permissions granted to the founder, Sky Mavis, a Vietnamese Blockchain Developer Company; giving them the ability to sign transactions (during a time of heavy transaction load) were not revoked and the hackers were able to sign in to those systems and then had the ability to validate blockchain transactions.  Sky Mavis has offered to try to repay those who lost out.  Luckily the in-game tokens SLP and AXS that players earn were not hacked or affected nor was the was the Ethereum Blockchain.  Bugs in code and any errors allow hackers to exploit.  This case was due to the error of Axie Dao, the decentralized organization that oversees the cryptocurrencies used in the Axie Infinity. 

What is a validator node?  Nodes are technically a computer or electronic device running software and they maintain a full or partial copy of the blockchain and employ their computing power to power and confirm transactions.  Nodes relay information through consensus protocol.  Each cryptocurrency has its own nodes.  

What is protocol?  It is basically a set of rules that allow data to be shared between computers for cryptocurrencies.  It is not new.  An example is how the internet email works.  It is based on several sets of protocol and the HTTP you see at the beginning of any URL stands for Hypertext Transfer Protocol.  In the case of cryptocurrencies, protocols allow cryptos to run across networks of computers with no central authority. 

Bugs in code allow hackers to exploit and some hacks are due to developers of code copy pasting pieces of different protocols that then lead to potential hacks if there are any typos or bugs in the code.  Extreme diligence is needed to certify that code is free from bugs and errors and copy pasting any thing can lead to mistakes.  Hopefully in the near future we will have a governing or certifying organization that developers and the public can turn to to be sure that code has no errors and this would lend more security to the entire Blockchain developers of new coins and protocols and something we all could greatly benefit from.