From ec383d97847f31712c1aa020ed15c44cb797e65a Mon Sep 17 00:00:00 2001
From: "Nikita P. Nazarov" <n.nazarov@izsoc.ru>
Date: Mon, 12 Oct 2020 18:52:28 +0300
Subject: [PATCH] Detects Obfuscated Powershell via Stdin in Scripts

---
 .../win_invoke_obfuscation_via_stdin.yml      | 23 +++++++++++++++++++
 1 file changed, 23 insertions(+)
 create mode 100644 rules/windows/process_creation/win_invoke_obfuscation_via_stdin.yml

diff --git a/rules/windows/process_creation/win_invoke_obfuscation_via_stdin.yml b/rules/windows/process_creation/win_invoke_obfuscation_via_stdin.yml
new file mode 100644
index 000000000..8f6466f93
--- /dev/null
+++ b/rules/windows/process_creation/win_invoke_obfuscation_via_stdin.yml
@@ -0,0 +1,23 @@
+title: Invoke-Obfuscation Via Stdin
+id: 9c14c9fa-1a63-4a64-8e57-d19280559490
+description: Detects Obfuscated Powershell via Stdin in Scripts
+status: experimental
+author: Nikita Nazarov, oscd.community
+date: 2020/10/12
+references:
+    - https://github.com/Neo23x0/sigma/issues/1009 #(Task28)
+tags:
+    - attack.defense_evasion
+    - attack.t1027
+    - attack.execution
+    - attack.t1059.001
+logsource:
+    category: process_creation
+    product: windows
+detection:
+    selection:
+        - CommandLine|re: '(?i).*(set).*&&\s?set.*(environment|invoke|\${?input).*&&.*"'
+    condition: selection
+falsepositives:
+    - Unknown
+level: high