Unhacked Challenge :: Schnoodle

08/29/2022

Schnoodle?

schnoodle is a dao on ethereum mainnet, governed by the SNOOD token.

After running smoothly for its first ~year, on 6/18, the ETH-SNOOD uniswap pair was drained for over 100 ETH.

• token (proxy): 0xd45740ab9ec920bedbd9bab2e863519e59731941
• token (implementation): 0xeac2a259f3ebb8fd1097aeccaa62e73b6e43d5bf
• uniswap pair 0x0f6b0960d2569f505126341085ed7f0342b67dae

Review the code in this repo, find the exploit, and recover > 100 ETH.

(hint: the issue is in the token implementation, so focus on src/SchnoodleV9.sol and src/imports/SchnoodleV9Base.sol. no need to look at the other files)

How to play

1. Fork this repo and clone it locally.

2. Create an .env file with an environment variable for ETH_RPC_URL (or add the rpc url directly into the test file).

3. Review the code in the src/ folder, which contains all the code at the time of the hack. you can explore the state of the contract before the hack using block 14983600. ex: cast call --rpc-url $ETH_RPC_URL --block 14983600 0xd45740ab9ec920bedbd9bab2e863519e59731941 "getFarmingFund()"

4. When you find an exploit, code it up in SchnoodleHack.t.sol. run the test with forge test -vvv. the test will pass if you succeed.

5. Post on twitter for bragging rights and tag @unhackedctf. no cheating.

Breaking Down The Exploit

// TODO

Source: src/SchnoodleV9.sol. Created using carbon.now.sh

Shilling @unhacked

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