During a security audit of a smart contract, the auditor finds that a function allows users to withdraw more than their balance due to an arithmetic error. Which remediation is most appropriate?

Use a safe math library that reverts on overflow or underflow

Increase the gas limit for the function

Change the function to be private

Add a reentrancy guard to the function

Which regulatory compliance requirement is particularly challenging for public blockchains due to their immutable nature?

The requirement to conduct regular security audits

The right to erasure (right to be forgotten)

The requirement to maintain transaction logs

The requirement to use strong encryption

What is the primary purpose of an incident response plan in a blockchain environment?

To replace the need for security monitoring tools

To ensure that blockchain transactions are irreversible

To provide a structured approach for detecting, responding to, and recovering from security incidents

To prevent all security incidents from ever occurring

A blockchain consortium wants to ensure that all member organizations follow the same security procedures for key management and incident reporting. Which governance mechanism would be most effective?

Adopt a formal security policy and require all members to sign a binding agreement

Implement a bug bounty program for external researchers

Rely on each member's existing internal security policies

Use a public blockchain to increase transparency

A developer is writing a smart contract that calculates rewards based on user deposits. The contract uses uint256 variables. A security review warns that the reward calculation could wrap around to a very large number if the deposit is extremely large. Which practice would best prevent this?

Use a random number generator to assign rewards.

Use SafeMath library or Solidity 0.8+ built-in overflow checks.

Use a smaller data type like uint8 to reduce the maximum value.

Add a comment in the code warning about overflow.

EC-CouncilBlockchain Fintech Certification

Domain 8Objective 3

Mitigating Blockchain Attacks and Security Practices BFC Practice Questions (Page 9)

Part of the Governance, Compliance, and Risk Management domain, which makes up ~12% of our current practice bank.

48questions here

10free pages

8concepts

Questions 41–45

41application · medium
During a security audit of a smart contract, the auditor finds that a function allows users to withdraw more than their balance due to an arithmetic error. Which remediation is most appropriate?
Select an answer first
42foundation · easy
Which regulatory compliance requirement is particularly challenging for public blockchains due to their immutable nature?
Select an answer first
43foundation · easy
What is the primary purpose of an incident response plan in a blockchain environment?
Select an answer first
44application · medium
A blockchain consortium wants to ensure that all member organizations follow the same security procedures for key management and incident reporting. Which governance mechanism would be most effective?
Select an answer first
45application · medium
A developer is writing a smart contract that calculates rewards based on user deposits. The contract uses uint256 variables. A security review warns that the reward calculation could wrap around to a very large number if the deposit is extremely large. Which practice would best prevent this?
Select an answer first

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