{"id":"96cd126d-f970-49c4-848a-da3a09f55c55","title":"Potential PowerShell Obfuscation Using Alias Cmdlets","description":"Detects Set-Alias or New-Alias cmdlet usage. Which can be use as a mean to obfuscate PowerShell scripts","author":"frack113","status":"test","level":"low","date":"2023-01-08","modified":"2025-10-22","tags":["attack.execution","attack.stealth","attack.t1027","attack.t1059.001"],"technique_ids":["T1027","T1059.001"],"logsource":{"product":"windows","category":"ps_script","definition":"Requirements: Script Block Logging must be enabled"},"falsepositives":["Unknown"],"references":["https://github.com/1337Rin/Swag-PSO"],"source_path":"rules/windows/powershell/powershell_script/posh_ps_susp_set_alias.yml","source_sha256":"5554fe86ff8f718c48c30bb79ede18ebbe8a396256ebfe9bd3f396e890050090","source_url":"https://github.com/anpa1200/sigma/blob/b249e9683190cffdcaf188ccbfb90bf4759844e1/rules/windows/powershell/powershell_script/posh_ps_susp_set_alias.yml","license":"Detection Rule License 1.1","license_url":"https://github.com/SigmaHQ/Detection-Rule-License/blob/main/LICENSE.Detection.Rules.md","yaml":"title: Potential PowerShell Obfuscation Using Alias Cmdlets\nid: 96cd126d-f970-49c4-848a-da3a09f55c55\nrelated:\n    - id: e8314f79-564d-4f79-bc13-fbc0bf2660d8\n      type: derived\nstatus: test\ndescription: Detects Set-Alias or New-Alias cmdlet usage. Which can be use as a mean to obfuscate PowerShell scripts\nreferences:\n    - https://github.com/1337Rin/Swag-PSO\nauthor: frack113\ndate: 2023-01-08\nmodified: 2025-10-22\ntags:\n    - attack.execution\n    - attack.stealth\n    - attack.t1027\n    - attack.t1059.001\nlogsource:\n    product: windows\n    category: ps_script\n    definition: 'Requirements: Script Block Logging must be enabled'\ndetection:\n    selection:\n        ScriptBlockText|contains:\n            - 'Set-Alias '\n            - 'New-Alias '\n    filter_main_cim:\n        ScriptBlockText:\n            - 'Set-Alias -Name ncms -Value New-CimSession -Option ReadOnly, AllScope -ErrorAction SilentlyContinue'\n            - 'Set-Alias -Name gcls -Value Get-CimClass -Option ReadOnly, AllScope -ErrorAction SilentlyContinue'\n            - 'Set-Alias -Name ncso -Value New-CimSessionOption -Option ReadOnly, AllScope -ErrorAction SilentlyContinue'\n            - 'Set-Alias -Name gcms -Value Get-CimSession -Option ReadOnly, AllScope -ErrorAction SilentlyContinue'\n            - 'Set-Alias -Name rcms -Value Remove-cimSession -Option ReadOnly, AllScope -ErrorAction SilentlyContinue'\n            - 'Set-Alias -Name rcie -Value Register-CimIndicationEvent -Option ReadOnly, AllScope -ErrorAction SilentlyContinue'\n            - 'Set-Alias -Name gcai -Value Get-CimAssociatedInstance -Option ReadOnly, AllScope -ErrorAction SilentlyContinue'\n            - 'Set-Alias -Name gcim -Value Get-CimInstance -Option ReadOnly, AllScope -ErrorAction SilentlyContinue'\n            - 'Set-Alias -Name scim -Value Set-CimInstance -Option ReadOnly, AllScope -ErrorAction SilentlyContinue'\n            - 'Set-Alias -Name ncim -Value New-CimInstance -Option ReadOnly, AllScope -ErrorAction SilentlyContinue'\n            - 'Set-Alias -Name rcim -Value Remove-cimInstance -Option ReadOnly, AllScope -ErrorAction SilentlyContinue'\n            - 'Set-Alias -Name icim -Value Invoke-CimMethod -Option ReadOnly, AllScope -ErrorAction SilentlyContinue'\n    condition: selection and not 1 of filter_main_*\nfalsepositives:\n    - Unknown\nlevel: low\n","validation":"yaml_parsed_not_backend_compiled_or_live_validated","techniques":[{"key":"enterprise/T1027","id":"T1027","name":"Obfuscated Files or Information","page":"techniques/enterprise/T1027/"},{"key":"enterprise/T1059.001","id":"T1059.001","name":"PowerShell","page":"techniques/enterprise/T1059.001/"}],"data_path":"data/detection-rules/96cd126d-f970-49c4-848a-da3a09f55c55.json","kind":"sigma"}