These programs let authorized transactions agreements be used by unknown parties without having the need of a central authority. In simple terms, the code is in itself a final party of the trade it is presenting, the program controls all the execution aspects, also provides an immutable evidentiary audit chain of transactions, both irreversible and trackable. As per the paper and researchers, "since smart contracts are not easily upgradable, auditing the contract's source pre-deployment, and deploying a bug-free contract is even more important than in the case of traditional software."

It aims to find inconsistencies in smart contracts, that allows an attacker to meddle with execution order or transactions, affecting control flow in a single transaction, for instance, reentrancy. Sailfish is a tool that converts a contract into a dependency graph, capturing control and data flow relations between state-changing instructions and storage variables of a smart contract. The tool helps to find potential inconsistencies. The researchers analyzed Sailfish on 89,853 contracts retrieved from Etherscan. 

Finding forty-seven zero-day vulnerabilities that can be exploited to extract Ether and might also comprise application-specific metadata. This will include vulnerable contracts implementing a house tracker that may be exploited so that house owners can do multiple active listings. "This is not the first time problematic smart contracts have attracted attention from academia. In September 2020, Chinese researchers designed a framework for categorizing known weaknesses in smart contracts with the goal of providing a detection criterion for each of the bugs," reports the hacker news.