Blockchain Security Training Risk Mitigation 3

Question 1

Which strategy best mitigates the risk of a hot wallet being drained on an exchange?

Accepted Answer

Keeping the majority of funds in cold storage and only operational amounts hot

Answer

Cold storage keeps the bulk of funds offline and out of reach of online attackers.

Question 2

A smart contract uses external calls. Which pattern mitigates reentrancy risk?

Accepted Answer

Checks-Effects-Interactions ordering with a reentrancy guard

Answer

Updating state before external calls and using a guard prevents reentrant withdrawals.

Question 3

What is the main risk-mitigation benefit of formal verification for a critical contract?

Accepted Answer

It mathematically proves the code meets specified properties

Answer

Formal verification proves specified properties hold for all inputs, catching subtle logic flaws.

Question 4

Which measure best mitigates governance-token attack risk where an attacker borrows tokens to pass a malicious proposal?

Accepted Answer

Requiring a voting delay and snapshot before flash-loaned votes can count

Answer

Snapshots and voting delays prevent flash-loaned tokens from being used to vote.

Question 5

How does a phased or canary deployment mitigate risk for a new protocol version?

Accepted Answer

It exposes a small portion of users/funds first to limit blast radius

Answer

Limiting initial exposure contains damage if the new version has a flaw.

Blockchain Practice Test