Input Validation Errors

Input validation errors happen when a smart contract fails to properly verify the data provided by a user or an external source, allowing for unexpected or malicious behavior. In cross-chain bridges, this often involves failing to check if a transaction amount is positive, if the recipient address is valid, or if the proof provided for a cross-chain transfer is authentic.

An attacker can exploit these gaps to manipulate bridge balances or divert funds to their own wallets. Proper input validation is the first line of defense in smart contract security, requiring developers to sanitize all incoming data against a strict set of expected formats and values.

Failure to implement this leads to severe vulnerabilities that are often easily exploited by automated bots.