Sigma rule: User Shell Folders Registry Modification via CommandLine

Rule

Title

User Shell Folders Registry Modification via CommandLine

Status

experimental

Level

high

Author

Swachchhanda Shrawan Poudel (Nextron Systems)

Date

2026-01-05

File

rules/windows/process_creation/proc_creation_win_user_shell_folders_registry_modification.yml

Commit

ccbb0369507f796db0b0ae6854c8a2be471b9d84

Detects modifications to User Shell Folders registry values via reg.exe or PowerShell, which could indicate persistence attempts.
Attackers may modify User Shell Folders registry values to point to malicious executables or scripts that will be executed during startup.
This technique is often used to maintain persistence on a compromised system by ensuring that malicious payloads are executed automatically.

Log source

product

windows

category

process_creation

Detection

selection_img:
    - Image|endswith:
          - '\powershell.exe'
          - '\pwsh.exe'
          - '\reg.exe'
    - OriginalFileName:
          - 'powershell.exe'
          - 'pwsh.dll'
          - 'reg.exe'
selection_cli_action:
    CommandLine|contains:
        - ' add ' # reg.exe modification
        - 'New-ItemProperty'
        - 'Set-ItemProperty'
        - 'si ' # short for Set-ItemProperty
selection_cli_paths_root:
    CommandLine|contains:
        - '\Software\Microsoft\Windows\CurrentVersion\Explorer\Shell Folders'
        - '\Software\Microsoft\Windows\CurrentVersion\Explorer\User Shell Folders'
selection_cli_paths_suffix:
    CommandLine|contains: 'Startup' # covers both 'Startup' and 'Common Startup'
condition: all of selection_*

False positives (as the rule lists them)

• Usage of reg.exe or PowerShell to modify User Shell Folders for legitimate purposes; but rare.

Tags

• attack.persistence
• attack.privilege-escalation
• attack.defense-impairment
• attack.t1547.001
• attack.t1112

MITRE ATT&CK ids this rule names

• T1112
• T1547.001

Related rules

• 9c226817-8dc9-46c2-a58d-66655aafd7dc (similar)

References

• https://www.welivesecurity.com/en/eset-research/muddywater-snakes-riverbank/

Read on 2026-11-03T00:58:21.399Z under licence sigma-drl-1.1@d5f4c36a from https://github.com/SigmaHQ/sigma/blob/ccbb0369507f796db0b0ae6854c8a2be471b9d84/rules/windows/process_creation/proc_creation_win_user_shell_folders_registry_modification.yml