The ad tech supply chain is the network of brokers, exchanges, and platforms that carries an advertisement from an advertiser to a website or app publisher. In programmatic advertising, these parties can select and deliver ads through automated auctions, often in fractions of a second.
This chain matters to cyber security because ad content and targeting can pass through multiple intermediaries before it is rendered on a user’s device. If a component is abused or serves attacker-controlled content, advertising may become a route for tracking or attempted exploitation—including zero-click attacks, where processing content can trigger an exploit without a user clicking. Evidence that an ad reached a device does not, by itself, prove that the device was compromised. Defenders should include third-party ad infrastructure in their threat models and keep browsers, apps, and operating systems patched.