An overlay attack is a cyberattack technique where malicious software displays a fake screen or interface on top of a legitimate app or website. This deceptive overlay mimics the real app's appearance, tricking users into entering sensitive information like passwords, PINs, or credit card details. Once entered, this data is captured by attackers for fraudulent use. Overlay attacks are commonly used in mobile banking malware and phishing schemes, exploiting users' trust in familiar interfaces. Protecting against overlay attacks involves keeping devices updated, installing apps only from trusted sources, and being cautious of unexpected prompts for sensitive information.