Apple on Thursday issued a patch that addresses three recently discovered critical iOS zero-day vulnerabilities, and advised users to update their systems immediately. State-sponsored actors exploited the flaws to target United Arab Emirates human rights defender Ahmed Mansoor, and a Mexican journalist who reported on government corruption. Researchers at the University of Toronto's Citizen Lab and security firm Lookout discovered the vulnerabilities, which they dubbed "Trident," after investigating suspicious text messages sent to Mansoor.