While msg.sender refers to the address of the most recent caller (either an EOA or a contract), tx.origin refers to the EOA that originally initiated the transaction, regardless of the calls made in between. Using tx.origin can also expose a contract to phishing attacks. An attacker can create a malicious contract that tricks a user into interacting with it. If the user initiates a transaction with this malicious contract, tx.origin would point to the user’s EOA. The malicious contract can then call another contract that relies on tx.origin for authentication, and it would incorrectly authorize the action because it sees the original EOA (the victim) as the transaction origin. Octane recommends using msg.sender to verify the authenticity of a user instead, and will flag any potential abuses from the use of tx.origin.