TA0003 · PERSISTENCE
Screensaver
Adversaries may establish persistence by executing malicious content triggered by user inactivity. Screensavers are programs that execute after a configurable time of user inactivity and consist of Portable Executable (PE) files with a .scr file extension.
Detect it with
Monitor process execution and command-line parameters of .scr files. Monitor changes to screensaver configuration changes in the Registry that may not correlate with typical user behavior.
Why it matters on shift
Screensaver is one of the concrete ways adversaries achieve persistence. Recognising it in telemetry lets you name the technique in your ticket and pivot to what came before and after.
What to look for next
After persistence, the next tactic is usually Privilege Escalation. Search your telemetry for the transition before closing the ticket.
Kill-chain context