Sigma rule: File or Folder Permissions Modifications

Rule

Title

File or Folder Permissions Modifications

Status

test

Level

medium

Author

Jakob Weinzettl, oscd.community, Nasreddine Bencherchali (Nextron Systems)

Date

2019-10-23

Modified

2023-11-21

File

rules-threat-hunting/windows/process_creation/proc_creation_win_susp_file_permission_modifications.yml

Commit

ccbb0369507f796db0b0ae6854c8a2be471b9d84

Detects a file or folder's permissions being modified or tampered with.

Log source

product

windows

category

process_creation

Detection

selection_1:
    Image|endswith:
        - '\cacls.exe'
        - '\icacls.exe'
        - '\net.exe' # "grant" Option available when used with "net share"
        - '\net1.exe' # "grant" Option available when used with "net share"
    CommandLine|contains:
        - '/grant'
        - '/setowner'
        - '/inheritance:r' # Remove all inherited ACEs
selection_2:
    Image|endswith: '\attrib.exe'
    CommandLine|contains: '-r'
selection_3:
    Image|endswith: '\takeown.exe' # If this generates FP in your environment. Comment it out or add more suspicious flags and locations
filter_optional_dynatrace_1:
    CommandLine|endswith: 'ICACLS C:\ProgramData\dynatrace\gateway\config\connectivity.history /reset'
filter_optional_dynatrace_2:
    CommandLine|contains|all:
        - 'ICACLS C:\ProgramData\dynatrace\gateway\config\config.properties /grant :r '
        - 'S-1-5-19:F'
filter_optional_vscode:
    CommandLine|contains:
        - '\AppData\Local\Programs\Microsoft VS Code'
        - ':\Program Files\Microsoft VS Code'
filter_optional_avira:
    CommandLine|contains:
        - ':\Program Files (x86)\Avira'
        - ':\Program Files\Avira'
condition: 1 of selection_* and not 1 of filter_optional_*

False positives (as the rule lists them)

• Users interacting with the files on their own (unlikely unless privileged users).
• Dynatrace app

Tags

• attack.defense-impairment
• attack.t1222.001
• detection.threat-hunting

MITRE ATT&CK ids this rule names

• T1222.001

References

• https://github.com/redcanaryco/atomic-red-team/blob/f339e7da7d05f6057fdfcdd3742bfcf365fee2a9/atomics/T1222.001/T1222.001.md
• https://docs.microsoft.com/en-us/previous-versions/windows/it-pro/windows-server-2012-r2-and-2012/hh750728(v=ws.11)
• https://github.com/swagkarna/Defeat-Defender-V1.2.0/tree/ae4059c4276da6f6303b8f53cdff085ecae88a91

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