Meta launched Muse on September 8 as a personal AI agent, marketing it as “a safe, secure, private” assistant built “from the ground up” to handle all your errands. It has since surged to become the No. 1 free iPhone app in the U.S. While early reviews have mostly focused on how Muse handles its users’ own data, an investigation by Hunterbrook Media revealed a darker capability: what the agent can do with other people’s data. Over two days of testing, Hunterbrook found that Muse can be easily prompted to compile dossiers on Facebook and Instagram accounts belonging to members of vulnerable groups – including undocumented immigrants, transgender teachers, poll workers, Iranian dissidents, and women who said they had ordered abortion pills in states with abortion bans. Many of the accounts belonged to private individuals with no public persona.