There is disclosed in one example a computing apparatus, including: a hardware platform including a processor and a memory; a network interface; a user-space application including instructions to interact with a web site via a uniform resource locator (URL); and a security agent including instructions to: intercept an interaction of the user-space application with the web site; determine that the intercepted interaction is to send sensitive information to the web site; suspend the interaction; and assign a reputation to the URL.