order powershell_script

rules/windows/powershell/powershell_script/powershell_shellcode_b64.yml

@@ -0,0 +1,32 @@
+title: PowerShell ShellCode
+id: 16b37b70-6fcf-4814-a092-c36bd3aafcbd
+status: experimental
+description: Detects Base64 encoded Shellcode
+references:
+    - https://twitter.com/cyb3rops/status/1063072865992523776
+tags:
+    - attack.defense_evasion
+    - attack.privilege_escalation
+    - attack.t1055
+    - attack.execution
+    - attack.t1059.001
+    - attack.t1086  #an old one
+author: David Ledbetter (shellcode), Florian Roth (rule)
+date: 2018/11/17
+modified: 2020/12/01
+logsource:
+    product: windows
+    service: powershell
+    definition: Script block logging must be enabled
+detection:
+    selection:
+        EventID: 4104
+        ScriptBlockText|contains: 'AAAAYInlM'
+    selection2:
+        ScriptBlockText|contains:
+            - 'OiCAAAAYInlM'
+            - 'OiJAAAAYInlM'
+    condition: selection and selection2
+falsepositives:
+    - Unknown
+level: critical