Trojan.Win32.Siscos.bqe / Insecure Permissions

[malvuln <malvuln13 () gmail com>]

Discovery / credits: Malvuln - malvuln.com (c) 2021
Original source:
https://malvuln.com/advisory/a41431099989b44359273216072f8295.txt
Contact: malvuln13 () gmail com
Media: twitter.com/malvuln

Threat: Trojan.Win32.Siscos.bqe
Vulnerability: Insecure Permissions
Description: creates an insecure dir named "Windupdt" under c:\ drive and
grants change (C) permissions to the authenticated user group. Standard
users can rename "win32.dll" 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: a41431099989b44359273216072f8295
Vuln ID: MVID-2021-0127
Dropped files: win32.dll
Disclosure: 03/14/2021

Exploit/PoC:
C:\>cacls Windupdt
C:\Windupdt 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:\>cd Windupdt

C:\Windupdt>dir
 Volume in drive C has no label.

 Directory of C:\Windupdt

06/14/2012  11:47 PM           750,040 win32.dll
               1 File(s)        750,040 bytes



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