PowerShell Base64 Encoding

 1title: PowerShell Base64 Encoding
 2id: 1d3025d2-f965-42e2-8256-adaa1054613d
 3status: experimental
 4description: Looks for the execution of powershell.exe with command lines that includes
 5    the term base64. Inspired by the 2022 Red Canary Threat Detection report.
 6references:
 7    - https://redcanary.com/threat-detection-report/techniques/powershell/
 8author: Micah Babinski
 9date: 2022/11/03
10tags:
11    - attack.defense_evasion
12    - attack.t1140
13    - attack.execution
14    - attack.t1059.001
15logsource:
16    category: process_creation
17    product: windows
18detection:
19    selection:
20        CommandLine|contains: 'base64'
21        Image|endswith: '\powershell.exe'
22    condition: selection
23falsepositives:
24    - Windows Config Manager (https://wtfbins.wtf/1)
25level: high```

References

• PowerShell - Red Canary Threat Detection Report

  

  PowerShell reclaimed its place as the most prevalent technique we detected in 2023, as adversaries continue to abuse the framework.

  
  Read More

Related rules

• Base64 Encoding in CMD or Powershell
• Command Shell Obfuscated Commands
• Gootloader Stage 2 Registry Key Creation
• Powershell Obfuscation and Escape Characters
• Suspicious Powershell Cmdlets