HEUR.Trojan.Win32.Generic / Insecure Permissions

[malvuln <malvuln13 () gmail com>]

Discovery / credits: Malvuln - malvuln.com (c) 2021
Original source:
https://malvuln.com/advisory/1a98a0a769e7351ba16e1b91e9f26692.txt
Contact: malvuln13 () gmail com
Media: twitter.com/malvuln

Threat: HEUR.Trojan.Win32.Generic
Vulnerability: Insecure Permissions
Description: The malware creates an insecure dir named "RECYCLER" 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: 1a98a0a769e7351ba16e1b91e9f26692
Vuln ID: MVID-2021-0179
Dropped files: svchost2.exe
Disclosure: 04/21/2021


Exploit/PoC:
C:\>cacls RECYCLER
C:\RECYCLER 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:\>dir RECYCLER
 Volume in drive C has no label.

 Directory of C:\RECYCLER

06/16/2012  02:32 AM            49,152 svchost2.exe
               1 File(s)         49,152 bytes


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