Sigma rule: PowerShell ShellCode

A detection rule from the SigmaHQ repository, shown as its author published it. Dataset version ref-2f1a1fabb61b, updated 2024-01-25T00:00:00.000Z.

Rule

Title
PowerShell ShellCode
Status
test
Level
high
Author
David Ledbetter (shellcode), Florian Roth (Nextron Systems)
Date
2018-11-17
Modified
2024-01-25
File
rules/windows/powershell/powershell_script/posh_ps_shellcode_b64.yml
Commit
ccbb0369507f796db0b0ae6854c8a2be471b9d84

Detects Base64 encoded Shellcode

Log source

product
windows
category
ps_script
definition
Requirements: Script Block Logging must be enabled

Detection

selection:
    ScriptBlockText|contains:
        - 'OiCAAAAYInlM'
        - 'OiJAAAAYInlM'
condition: selection

False positives (as the rule lists them)

  • Unknown

Tags

  • attack.privilege-escalation
  • attack.stealth
  • attack.t1055
  • attack.execution
  • attack.t1059.001

MITRE ATT&CK ids this rule names

References

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/powershell/powershell_script/posh_ps_shellcode_b64.yml

Sources and licences

  • SigmaHQ

    "PowerShell ShellCode" by David Ledbetter (shellcode), Florian Roth (Nextron Systems) (SigmaHQ). Rule: https://github.com/SigmaHQ/sigma/blob/ccbb0369507f796db0b0ae6854c8a2be471b9d84/rules/windows/powershell/powershell_script/posh_ps_shellcode_b64.yml.
    Licensed under the Detection Rule License (DRL) 1.1: https://github.com/SigmaHQ/Detection-Rule-License

    Detection Rule License (DRL) 1.1

Cite this page

Dragons Eye Ransomware Tracker, "Sigma rule: PowerShell ShellCode",
entity page, dataset version ref-2f1a1fabb61b, updated 2024-01-25T00:00:00.000Z,
https://ransomware-tracker.com/detections/sigma/16b37b70-6fcf-4814-a092-c36bd3aafcbd (accessed 2026-11-03).
Underlying source: SigmaHQ rule 16b37b70-6fcf-4814-a092-c36bd3aafcbd, commit ccbb0369507f796db0b0ae6854c8a2be471b9d84.

Pages change. The dataset version identifies the data, but no archive of old versions is kept, so this citation cannot be replayed later.