Two U.S. government agencies have warned journalists, dissidents, and others about commercial surveillance software, saying the tools “access and retrieve virtually all content on a phone.”

In a recently released one-page document, the Department of State and the National Counterintelligence and Security Center advise potential targets of commercial surveillance software to take several measures to protect themselves. The warning comes after reports last year about the Pegasus surveillance tool sold by Israeli company NSO Group being used to spy on journalists, politicians, human rights activists, and other people.