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Security
Blockchain Developer
Security questions
10 questions on Security for blockchain developers, easiest first.
Medium
4
Spot the reentrancy bug
medium
Using tx.origin for auth
medium
Upgrading a proxy safely
medium
Overflow in Solidity 0.8
medium
Hard
6
Lending protocol price oracle
hard
Replaying a signed message
hard
First depositor in a vault
hard
Reentrancy through a view function
hard
Paying everyone in a loop
hard
delegatecall to user input
hard
