By the end of this lesson, you'll be able to:

Explain the various security vulnerabilities associated with closing program accounts incorrectly
Close program accounts safely and securely using native Rust
Close program accounts safely and securely using the Anchor `close` constraint

Lab: Check signers are correct before processing transactions

Lab: Check owners are correct before processing transactions

Lab: Check account data is correct before processing transactions

Lab: Ensure accounts can only be initialised once to prevent overriding existing data

Lab: Ensure accounts are distinct

Lab: Implement checks for correct account types

Lab: Ensure CPIs are only called by the correct program

Lab: Ensure bump seeds are always canonical

Lab: Ensure accounts that are closed can't be reused

Lab: Ensure PDA design avoids shared accounts