I will write you an official article on this topic.
Ethereum: Can a validator include transactions with invalid signatures?
On the Ethereum blockchain, validators play a crucial role in ensuring the integrity and security of the network. To achieve this, validators must include valid transactions in their blocks, which are then broadcast throughout the network. But what happens if a validator receives an invalid signature for a transaction? In this article, we will examine whether a validator can include such transactions.
Yellow Paper
According to the Ethereum Yellow Paper (Section 2.4), a validator’s decision to include a transaction in its block is based solely on the validity of the transaction itself, and not on information provided by other nodes or stakeholders. This means that if a validator receives an invalid signature for a transaction, it will still be included in the block.
The Case of Invalid Signatures
While the Yellow Paper specifically states that validators must have valid transactions, there are situations where an invalid signature can occur. For example:
- A malicious actor can create a transaction with an invalid signature and send it to a node on the network.
- A node can receive a transaction from an external source and attempt to add it to its local block.
Can a validator contain invalid signatures?
Based on the Yellow Paper, it appears that validators cannot include transactions with invalid signatures. The paper states that validators must verify the validity of each transaction before including it in their block. This ensures that only valid transactions are added to the chain.
However, this does not mean that validators cannot accept or verify invalid signatures from other nodes or sources. In fact, many Ethereum developers and researchers have explored ways to handle such cases, such as:
- Implementing additional verification mechanisms to detect invalid signatures.
- Using techniques such as optimistic consistency to allow partially valid transactions to be added to the block.
Conclusion
Overall, while the Yellow Paper provides clear guidance on how validators should include transactions in their blocks, it does not specifically address the possibility of including transactions with invalid signatures. However, many Ethereum developers and researchers have explored ways to handle such cases, and it is possible that future updates to the Yellow Paper will clarify this issue.
Ultimately, whether a validator is able to accept transactions with invalid signatures depends on the specific implementation and design of the blockchain network. While there may be theoretical limitations, currently validators cannot add invalid signatures to their blocks based solely on information provided by other nodes or stakeholders.