CBSA Blockchain Security and Privacy 4

Question 1

Which Hyperledger Fabric feature ensures that chaincode execution results are consistent across endorsing peers before being ordered?

Accepted Answer

Execute-Order-Validate (EOV) architecture

Answer

Fabric's Execute-Order-Validate architecture separates endorsement from ordering, allowing parallel simulation and ensuring deterministic results are validated before block commit.

Question 2

An oracle manipulation attack on a DeFi protocol most directly exploits which weakness?

Accepted Answer

Reliance on a single or manipulable off-chain price feed

Answer

Oracle manipulation attacks exploit contracts that use a single manipulable price source, allowing flash-loan attackers to distort the price feed and trigger unfair liquidations or mints.

Question 3

What does 'key ceremony' refer to in blockchain PKI security?

Accepted Answer

A formal, witnessed procedure for generating and splitting cryptographic root keys with audit controls

Answer

A key ceremony is a structured, multi-party event where root CA or master keys are generated with witnesses, HSMs, and documented procedures to prevent any single party from obtaining full control.

Question 4

Which attack targets the peer-to-peer network layer of a blockchain node by surrounding it with malicious peers to control all its inbound and outbound connections?

Accepted Answer

Eclipse attack

Answer

An eclipse attack isolates a target node by filling all its peer connection slots with adversary-controlled nodes, enabling double-spend attacks or denying it access to the honest chain.

Question 5

In the context of blockchain cryptography, what is a 'nonce' primarily used for in proof-of-work mining?

Accepted Answer

An arbitrary number miners iterate to find a hash meeting the difficulty target

Answer

Miners repeatedly change the nonce value in a block header and rehash until the resulting hash falls below the network's difficulty target, proving computational work.

(CBSA) Certified Blockchain Solution Architect Practice Test

(CBSA) Certified Blockchain Solution Architect Practice Test

CBSA Blockchain Security and Privacy 4