Google and Microsoft have pulled ModHeader, a popular header-editing extension with roughly 1.6 million installs across Chrome and Edge, after researchers found a hidden browsing-history collector built into its official store version. The collector was dormant. An empty allow-list kept it switched off, and no proof has emerged that it ever gathered or sent a single browsing domain. The

Give an AI assistant a memory and access to your inbox, and you hand an attacker a way to rewrite what it thinks it knows about you. A single email can trick that agent into saving a false "fact" about the user, hide the change, and quietly steer its answers in later sessions. When it works, the person reads an ordinary-looking reply and never learns their assistant was tampered with. The