Fundamentals of Blockchain Security Flashcards
7 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 7 Fundamentals of Blockchain Security flashcards as text
In public-key cryptography used by blockchains, which key is shared openly?
Answer: The public key
The public key (or derived address) is shared so others can verify signatures and send funds.
What is a Sybil attack in a blockchain network?
Answer: Flooding the network with fake identities to gain disproportionate influence
A Sybil attack uses many fake nodes or identities to subvert reputation or consensus systems.
How does Proof of Work deter attacks on a blockchain?
Answer: By requiring attackers to expend large computational resources
PoW makes attacks economically costly because rewriting history requires enormous computing power.
What is the main security trade-off of storing assets in a hot wallet?
Answer: It is internet-connected and more exposed to remote attacks
Hot wallets stay online for convenience but their connectivity increases exposure to hacking.
Which of the following is a key benefit of a cold storage wallet?
Answer: Private keys kept offline, away from network attacks
Cold storage keeps keys offline, drastically reducing the attack surface for remote theft.
What does a digital signature verify about a blockchain transaction?
Answer: The sender authorized it and the message was not altered
A signature confirms both authenticity of the sender and integrity of the signed data.
Why are seed phrases considered highly sensitive in wallet security?
Answer: They can regenerate all private keys and restore full wallet access
A seed phrase deterministically recreates every private key in a wallet, so anyone with it controls the funds.