Invoke-Obfuscation Via Stdin - Security

 1title: Invoke-Obfuscation Via Stdin - Security
 2id: 80b708f3-d034-40e4-a6c8-d23b7a7db3d1
 3related:
 4    - id: 487c7524-f892-4054-b263-8a0ace63fc25
 5      type: derived
 6status: test
 7description: Detects Obfuscated Powershell via Stdin in Scripts
 8references:
 9    - https://github.com/SigmaHQ/sigma/issues/1009 # (Task28)
10author: Nikita Nazarov, oscd.community
11date: 2020-10-12
12modified: 2022-11-29
13tags:
14    - attack.defense-evasion
15    - attack.t1027
16    - attack.execution
17    - attack.t1059.001
18logsource:
19    product: windows
20    service: security
21    definition: The 'System Security Extension' audit subcategory need to be enabled to log the EID 4697
22detection:
23    selection:
24        EventID: 4697
25        ServiceFileName|contains|all:
26            - 'set'
27            - '&&'
28        ServiceFileName|contains:
29            - 'environment'
30            - 'invoke'
31            - '${input)'
32    condition: selection
33falsepositives:
34    - Unknown
35level: high