Solana Token-2022 Security: The Hidden Attack Surface in Token Extensions Every DeFi Protocol Must Address

Solana's Token-2022 program — also known as Token Extensions — is reshaping how tokens work on Solana. Transfer hooks, confidential transfers, transfer fees, and permanent delegates introduce powerful primitives that the original SPL Token program never had. But with power comes an expanding attack surface that most DeFi protocols aren't ready for. After analyzing real audit findings, disclosed vulnerabilities, and the Neodyme security research on Token-2022, I've compiled the most critical security pitfalls every Solana developer needs to understand before integrating Token Extensions into their protocol. Why Token-2022 Changes Everything The original SPL Token program was simple: create mints, create accounts, transfer tokens. Every DeFi protocol on Solana was built around these predictable behaviors. Token-2022 breaks these assumptions. A token transfer is no longer just a balance update — it can now: Execute arbitrary code via transfer hooks Deduct fees via the transfer fee extensi