Toast Notification XML with External Image URL Constructed via PowerShell

Bryant Smith@flowstate

•updated Mar 25, 2026•0•30

Detects PowerShell constructing toast notification XML with an external HTTP image URL alongside WinRT toast API calls. When the notification is displayed the notification platform fetches the image, creating an outbound connection to an attacker-controlled server for delivery confirmation. Sourced from the toastnotify-bof repository incoming-call.xml and teams-security-alert.xml example payloads.