Ethereum smart contracts are self-executing programs stored on the Ethereum blockchain. They run when predefined conditions are met and can hold data, logic, or references to other resources. Because they are distributed and difficult to alter after deployment, they are often used to encode rules that can be checked by anyone.
In cyber security, that persistence can be abused. Attackers may use smart contracts to store pointers to malicious payloads, rotate infrastructure, or hide where a skimmer should fetch its next stage. This makes takedown harder because removing one web server may not remove the blockchain reference that leads to it. Defenders should treat blockchain-linked retrieval paths as part of the attack surface, monitor checkout scripts for unexpected outbound lookups, and look for changes in client-side dependencies that may signal a hidden delivery chain.