After the hard fork, ETH contracts suffered another round of attacks

In order to solve the DoS attack problem in the network, ETH (Ethereum fork) performed a hard fork on the 18th. However, about 24 hours later, a contract in ETH seemed to have been attacked by another round of attacks.

ETH developer Nick Johnson confirmed the news in a Reddit post:

Yes, the attacker launched EXP攻击（Expanse attack） , which we expected. The processing time varies from 1 to 3 seconds, depending on how powerful your node's CPU is (unlike the previous attack, this attack mainly targets processing power). The upcoming second hard fork will reset EXP, and then this type of attack will not be a big problem.

(Note: Expanse is a decentralized encrypted information, application and contract platform based on the ETH network. EXP is its platform token.)

Johnson said that they are currently unable to do anything about this attack because they checked the opcodes after the first hard fork and noticed that EXP was undervalued.

He said the developers are currently investigating.

Previously, we cached all account states in memory (about 180MB). Since the DoS attack, we can only cache the nearest reference node, and the attacker took advantage of this and increased the read pressure of geth by creating a large number of empty accounts.

According to user Finish-the-thought, the contract affected by the attack was a mining address that mined ETH 433 days ago.

ETH network transactions have been hit by spam attacks since September. The blocks created by this attack took up a lot of space, the hard disk read rate reached more than 50,000, and the transaction confirmation time was slowed down to between 20 and 60 seconds.