Donation Attacks used in price manipulation

[sambacha]

Price Manipulation via Donation Attacks

example from CREAM Finance attack

Here is the exploit: donate double existing amount yUSD to yUSD Vault. This doubles the value of yUSD so crYUSD collateral have doubled in value

https://github.com/Crypto-Virus/cream-finance-exploit-example/blob/master/contracts/Attack.sol