Blockstream on Nostr: The Bybit hack has revived long-standing debates about the security trade-offs built ...
The Bybit hack has revived long-standing debates about the security trade-offs built into the Ethereum protocol. We cover its reliance on complex, stateful smart contracts, the systemic challenges in its design—and how Bitcoin avoids these pitfalls. 🧵
https://blog.blockstream.com/the-risks-of-expressive-smart-contracts-lessons-from-the-latest-ethereum-hack/
Multisig serves as a fundamental security layer by requiring more than one signer to move funds. On Bitcoin and the LiquidNetwork (nprofile…0cnd) , implementing this is simple thanks to native opcodes (e.g., OP_CHECKMULTISIG) or Schnorr-based interactivity, keeping the code surface small and secure.
On Ethereum, however, developers must create custom code to emulate multisig—leading to complexity, increased computational demands, and potentially flawed interfaces.
Ethereum contracts must manage on-chain state, handle reentrancy (where an attacker calls a contract in the middle of its own execution), and ensure that the logic for multiple signers is correctly enforced.
Ethereum also uses an account-based model with a universal state tree, meaning each contract update can influence or interact with data used by other contracts.
Mistakes in these areas can introduce critical vulnerabilities, as we have seen with high-profile incidents like the Ethereum Parity wallet hack in 2017 and now with Bybit.
https://cointelegraph.com/news/parity-multisig-wallet-hacked-or-how-come
In contrast, Bitcoin's UTXO model localizes state changes to individual transactions, reducing the risk that one contract's flaw will leak into another's operation.
While Ethereum contends with repeated contract exploits, Bitcoin and its sidechains are evolving toward more robust multisig approaches. For example, cryptographic schemes like MuSig aggregate multiple signatures into one, making multisig transactions look like standard singlesig. This benefits both privacy and efficiency.
Looking further ahead, the proposed Simplicity language on the LiquidNetwork (nprofile…0cnd) aims to provide the flexibility of a higher-level scripting language while retaining Bitcoin's careful approach to security.
https://blog.blockstream.com/simplicity-arrives-on-liquid-testnet/
Rather than offering Turing-complete smart contracts, Simplicity focuses on formally verifiable scripts (easier to audit and prove correct) and advanced features like covenants and custom sighash types, all designed to avoid the pitfalls seen with the EVM's unbounded computations.
As the blockchain industry matures, it's increasingly evident that security must be a top-level design choice—not a feature layered on after the fact. This is why we firmly believe that Bitcoin offers the best foundation for capital markets and finance.
https://blog.blockstream.com/why-bitcoins-utxo-model-is-best-for-blockchain-based-finance/
For a more comprehensive analysis of the Bybit hack and the underlying flaws in Ethereum's design, read our full report:
https://blog.blockstream.com/the-risks-of-expressive-smart-contracts-lessons-from-the-latest-ethereum-hack/
https://blog.blockstream.com/the-risks-of-expressive-smart-contracts-lessons-from-the-latest-ethereum-hack/
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Multisig serves as a fundamental security layer by requiring more than one signer to move funds. On Bitcoin and the LiquidNetwork (nprofile…0cnd) , implementing this is simple thanks to native opcodes (e.g., OP_CHECKMULTISIG) or Schnorr-based interactivity, keeping the code surface small and secure.
On Ethereum, however, developers must create custom code to emulate multisig—leading to complexity, increased computational demands, and potentially flawed interfaces.

Ethereum contracts must manage on-chain state, handle reentrancy (where an attacker calls a contract in the middle of its own execution), and ensure that the logic for multiple signers is correctly enforced.
Ethereum also uses an account-based model with a universal state tree, meaning each contract update can influence or interact with data used by other contracts.

Mistakes in these areas can introduce critical vulnerabilities, as we have seen with high-profile incidents like the Ethereum Parity wallet hack in 2017 and now with Bybit.
https://cointelegraph.com/news/parity-multisig-wallet-hacked-or-how-come
In contrast, Bitcoin's UTXO model localizes state changes to individual transactions, reducing the risk that one contract's flaw will leak into another's operation.

While Ethereum contends with repeated contract exploits, Bitcoin and its sidechains are evolving toward more robust multisig approaches. For example, cryptographic schemes like MuSig aggregate multiple signatures into one, making multisig transactions look like standard singlesig. This benefits both privacy and efficiency.
Looking further ahead, the proposed Simplicity language on the LiquidNetwork (nprofile…0cnd) aims to provide the flexibility of a higher-level scripting language while retaining Bitcoin's careful approach to security.
https://blog.blockstream.com/simplicity-arrives-on-liquid-testnet/
Rather than offering Turing-complete smart contracts, Simplicity focuses on formally verifiable scripts (easier to audit and prove correct) and advanced features like covenants and custom sighash types, all designed to avoid the pitfalls seen with the EVM's unbounded computations.
As the blockchain industry matures, it's increasingly evident that security must be a top-level design choice—not a feature layered on after the fact. This is why we firmly believe that Bitcoin offers the best foundation for capital markets and finance.
https://blog.blockstream.com/why-bitcoins-utxo-model-is-best-for-blockchain-based-finance/
For a more comprehensive analysis of the Bybit hack and the underlying flaws in Ethereum's design, read our full report:
https://blog.blockstream.com/the-risks-of-expressive-smart-contracts-lessons-from-the-latest-ethereum-hack/
