Trojan-Dropper.Win32.Dycler.vrp Insecure Permissions

2021-04-28T00:00:00
ID PACKETSTORM:162355
Type packetstorm
Reporter malvuln
Modified 2021-04-28T00:00:00

Description

                                        
                                            `Discovery / credits: Malvuln - malvuln.com (c) 2021  
Original source: https://malvuln.com/advisory/1d6d6d3c077250b7b3ad053e71054ecc.txt  
Contact: malvuln13@gmail.com  
Media: twitter.com/malvuln  
  
Threat: Trojan-Dropper.Win32.Dycler.vrp  
Vulnerability: Insecure Permissions  
Description: The malware creates an insecure dir named "Drivers" under c:\ drive and grants change (C) permissions to the authenticated user group. Standard users can rename the executables 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: 1d6d6d3c077250b7b3ad053e71054ecc  
Vuln ID: MVID-2021-0186  
Dropped files: dlhost.exe, hgo.bat  
Disclosure: 04/27/2021  
  
  
Exploit/PoC:  
C:\>cacls Drivers  
C:\Drivers BUILTIN\Administrators:(OI)(CI)(ID)F  
NT AUTHORITY\SYSTEM:(OI)(CI)(ID)F  
BUILTIN\Users:(OI)(CI)(ID)R  
NT AUTHORITY\Authenticated Users:(ID)C  
NT AUTHORITY\Authenticated Users:(OI)(CI)(IO)(ID)C  
  
  
  
C:\Drivers>attrib -s -h symbols  
  
C:\Drivers>dir symbols  
Volume in drive C has no label.F  
  
Directory of C:\Drivers\symbols  
  
10/13/2011 09:50 AM 1,710,592 dlhost.exe  
10/13/2011 09:52 AM 79 hgo.bat  
04/26/2021 08:36 PM <DIR> Microsoft.VC90.CRT  
2 File(s) 1,710,671 bytes  
3 Dir(s) 6,918,037,504 bytes free  
  
  
  
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