offensive security
Screensaver Hijack
Hijacking screensaver for persistence.
Execution
To achieve persistence, the attacker can modify
SCRNSAVE.EXE value in the registry HKCU\Control Panel\Desktop\ and change its data to point to any malicious file. In this test, I will use a netcat reverse shell as my malicious payload:
Let's update the registry:
The same could be achieved using a native Windows binary reg.exe:
Observations
Note the process ancestry on the victim system - the reverse shell process traces back to winlogon.exe as the parent process, which is responsible for managing user logons/logoffs. This is highly suspect and should warrant a further investigation:
References
Event Triggered Execution: Screensaver, Sub-technique T1546.002 - Enterprise | MITRE ATT&CK®
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Last modified 3yr ago
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