FREE Blockchain Developer Blockchain Security and Vulnerabilities Questions and Answers Flashcards
6 cards from real Blockchain Technology practice questions. Tap to flip, then mark Knew It or Still Learning — missed cards come back until you master them.
Read the first 6 FREE Blockchain Developer Blockchain Security and Vulnerabilities Questions and Answers flashcards as text
What is a logic bomb vulnerability in a smart contract?
Answer: Hidden malicious code that activates under specific conditions set by the developer
A logic bomb is intentionally hidden code that executes harmful actions when predetermined conditions are met, often planted by a malicious developer.
Why is the delegatecall function considered dangerous when used with untrusted contracts?
Answer: It allows the called contract to execute code in the context of the calling contract's storage
Delegatecall executes the target contract's code but uses the calling contract's storage and context, so a malicious target can overwrite critical storage variables.
What vulnerability does the absence of access control on a selfdestruct function create?
Answer: Anyone can destroy the contract and send its remaining ETH to an arbitrary address
Without proper access control, any account can call selfdestruct, permanently removing the contract and redirecting its ETH balance to any specified address.
How does an oracle manipulation attack compromise a DeFi protocol?
Answer: By feeding false price data to a protocol that relies on external data sources for critical calculations
Oracle manipulation attacks feed incorrect price data to protocols, enabling attackers to borrow against inflated collateral or liquidate positions at artificial prices.
What is storage collision in the context of proxy-based upgradeable contracts?
Answer: When the proxy and implementation contracts map different variables to the same storage slot
Storage collision occurs when a proxy and its implementation contract use the same storage slot for different variables, causing data corruption during delegatecall execution.
What is the impact of an uninitialized storage pointer vulnerability in older Solidity versions?
Answer: It allows an attacker to overwrite arbitrary storage slots by manipulating a struct or array that defaults to storage slot 0
In older Solidity versions, uninitialized local storage variables defaulted to storage slot 0, allowing accidental or intentional overwriting of critical contract state.