Crypto security is the collection of technologies, practices, and operational controls used to protect crypto assets, wallets, accounts, transactions, smart contracts, and blockchain infrastructure from theft, unauthorized access, manipulation, and other attacks.

Unlike traditional financial systems, cryptocurrency security often depends directly on the asset holder. Losing a private key or seed phrase can permanently remove access to funds when no alternative recovery mechanism exists.

Crypto security operates at several levels. At the blockchain level, consensus, network security, and transaction validation are critical. At the user level, self-custody, key protection, and authentication matter. At the application level, smart-contract security, access control, and code review are essential.

Main security layers

  • Blockchain security — protection of the blockchain chain, consensus mechanism, and network nodes.
  • Wallet security — protection of private keys, seed phrases, and devices used for transaction signing.
  • Account security — protection of accounts through authentication and additional security factors.
  • Application security — identification and mitigation of vulnerabilities in dApps, exchanges, and smart contracts.

Common threats include phishing, social engineering, brute-force attacks, key theft, malware, and attacks against blockchain consensus such as 51% attacks and Sybil attacks.

Crypto security is therefore not a single technology. It is a layered security model in which protocol security, software security, infrastructure security, and user behavior all affect the final level of protection.