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Web application security

Blockchain Developer

Web application security questions

10 questions on Web application security for blockchain developers, easiest first.

Medium 4

Spot the reentrancy bugmedium
Using tx.origin for authmedium
Upgrading a proxy safelymedium
Overflow in Solidity 0.8medium

Hard 6

Lending protocol price oraclehard
Replaying a signed messagehard
First depositor in a vaulthard
Reentrancy through a view functionhard
Paying everyone in a loophard
delegatecall to user inputhard

More Blockchain Developer skills

Solidity and the EVM 68 Smart contract security 33 Blockchain and DeFi 25 Security fundamentals and cryptography 13

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