A verification channel is a separate communication path used to confirm a sensitive request before it is approved. It should be different from the original message path, especially when the request involves money transfers, password resets, bank detail changes, or any action that benefits from urgency or secrecy.
In cyber security, verification channels help break social engineering attacks. If an attacker impersonates an executive in a chat app or email, the defender should confirm the request through a different medium, such as a phone call to a known number or an in-person check. This reduces the chance that a fraudulent message can use the same compromised account or conversation thread to appear legitimate. Good verification channels are preplanned, trusted, and hard for an attacker to intercept. They are a core control for CEO fraud, business email compromise, and other high-risk requests where trust alone is not enough.