Malware is software that harms, exploits, or steals from a user’s device. It can take the form of a virus, ransomware, spyware, trojans, and more. Advertising, on the other hand, is meant to promote products, services, or content through banners, pop-ups, or native placements. Malvertising sits right at the intersection of the two. It’s when bad actors embed malware inside ads or use ad infrastructure to deliver malicious code, often on legitimate websites. The ad looks normal, but once it loads, it can infect the user’s device without a single click.