CosaNostra Builder Insecure Permissions

`Discovery / credits: Malvuln - malvuln.com (c) 2022  
Original source: https://malvuln.com/advisory/61285c988de52b7c067fb2e703f2ab83.txt  
Contact: [email protected]  
Media: twitter.com/malvuln  
  
Threat: CosaNostra Builder   
Vulnerability: Insecure Permissions  
Description: The malware creates PE files with insecure permissions when writing to c:\ drive, granting change (C) permissions to the authenticated user group. Standard users can rename the executable dropped by the malware to disable it or replace it with their own executable. Then wait for a privileged user to logon to the infected machine to potentially escalate privileges.  
Type: PE32  
MD5: 61285c988de52b7c067fb2e703f2ab83  
Vuln ID: MVID-2022-0471  
Disclosure: 01/24/2022  
  
Exploit/PoC:  
C:\>cacls hate.exe  
C:\hate.exe BUILTIN\Administrators:(ID)F  
NT AUTHORITY\SYSTEM:(ID)F  
BUILTIN\Users:(ID)R  
NT AUTHORITY\Authenticated Users:(ID)C  
  
C:\>dir hate.exe  
Volume in drive C has no label.  
  
Directory of C:\  
  
01/23/2022 11:37 PM 112,140 hate.exe  
1 File(s) 112,140 bytes  
0 Dir(s) 27,572,977,664 bytes free  
  
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