Suspicious Copy From or To System Directory
Description
Detects a suspicious copy operation that tries to copy a program from system (System32, SysWOW64, WinSxS) directories to another on disk. Often used to move LOLBINs such as 'certutil' or 'desktopimgdownldr' to a different location with a different name in order to bypass detections based on locations.
Query · sigma
selection_img_cmd: Image|endswith: \cmd.exe CommandLine|contains: 'copy ' selection_img_pwsh: Image|endswith: - \powershell.exe - \pwsh.exe CommandLine|contains: - copy-item - ' copy ' - 'cpi ' - ' cp ' selection_img_other: - Image|endswith: - \robocopy.exe - \xcopy.exe - OriginalFileName: - robocopy.exe - XCOPY.EXE selection_target: CommandLine|re|i: \s['"]?C:\\Windows\\(?:System32|SysWOW64|WinSxS) filter_optional_avira: Image|endswith: \cmd.exe CommandLine|contains|all: - /c copy - \Temp\ - \avira_system_speedup.exe CommandLine|contains: - C:\Program Files\Avira\ - C:\Program Files (x86)\Avira\ condition: 1 of selection_img_* and selection_target and not 1 of filter_optional_*
Known false positives
- Depend on scripts and administrative tools used in the monitored environment (For example an admin scripts like https://www.itexperience.net/sccm-batch-files-and-32-bits-processes-on-64-bits-os/)
- When cmd.exe and xcopy.exe are called directly
- When the command contains the keywords but not in the correct order