Merge pull request #2538 from frack113/fix_detection

fix detection posh_ps_suspicious_iofilestream

rules/windows/powershell/powershell_script/posh_ps_suspicious_iofilestream.yml

@@ -3,6 +3,7 @@ id: 70ad982f-67c8-40e0-a955-b920c2fa05cb
 status: experimental
 description: Open a handle on the drive volume via the \\.\ DOS device path specifier and perform direct access read of the first few bytes of the volume.
 date: 2022/01/09
+modified: 2022/01/10
 author: frack113
 references:
     - https://github.com/redcanaryco/atomic-red-team/blob/master/atomics/T1006/T1006.md
@@ -15,7 +16,7 @@ detection:
         ScriptBlockText|contains|all:
             - New-Object 
             - IO.FileStream
-            - '"\\.\'
+            - '\\.\'
     condition: selection
 falsepositives:
     - Legitimate PowerShell scripts