Virtual Labs

Smart contract vulnerabilities (Re-entrance, Arithmetic overflow and underflow, Accessing private data)

What is a smart contract?

a: A legal document stored on a blockchain Explanation

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b: A self-executing contract with the terms of the agreement directly written into code Explanation

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c: A contract signed electronically using a smart card Explanation

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d: An agreement between two parties without any written documentation Explanation

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Which blockchain platform is commonly used for deploying smart contracts?

a: Ethereum Explanation

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b: Bitcoin Explanation

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c: Ripple Explanation

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d: Litecoin Explanation

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What is the main advantage of using smart contracts?

a: Increased security Explanation

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b: Decreased transparency Explanation

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c: Reduced automation Explanation

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d: Higher transaction costs Explanation

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What happens during an overflow attack on a smart contract?

a: A value drops below the minimum representable limit Explanation

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b: A function calls an untrusted contract recursively Explanation

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c: A value exceeds the maximum representable limit and wraps around Explanation

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d: Private data is accessed by external users Explanation

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What is a re-entrancy attack in the context of smart contracts?

a: An attack where private variables are read by external users Explanation

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b: An attack where a function recursively calls an untrusted contract to drain funds Explanation

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c: An attack where integer values exceed their maximum limit Explanation

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d: An attack where a contract fails due to insufficient gas Explanation

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Why is storing sensitive information like passwords in a smart contract a bad idea?

a: Because smart contracts are slow to process sensitive data Explanation

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b: Because blockchains are transparent, allowing anyone to read private variables Explanation

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c: Because smart contracts cannot store data securely Explanation

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d: Because passwords increase the gas cost of transactions Explanation

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