New FlutterShell Backdoor Malware Targets macOS Users Through Malvertising Campaign

Cybersecurity researchers have identified 'Operation FlutterBridge,' a malvertising campaign distributing a new backdoor called FlutterShell on macOS. This malware, developed using the Flutter framework, infects systems through deceptive desktop applications promoted via Google and YouTube advertisements. FlutterShell allows for remote command execution, file system interaction, and exfiltration of sensitive data, with recent detections confirmed in March 2026.