Original source: https://malvuln.com/advisory/d2ee6046fd47de321d1310dccacca92b.txt
Contact:
Media: twitter.com/malvuln
Threat: Backdoor.Win32.DarkKomet.artr
Vulnerability: Insecure Permissions
Description: The malware creates an hidden insecure dir named
"Windupdt" 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: d2ee6046fd47de321d1310dccacca92b
Vuln ID: MVID-2021-0182
Dropped files: winupdate.exe
Disclosure: 04/21/2021
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:\>dir Windupdt
Volume in drive C has no label.
Directory of C:\Windupdt
0 File(s) 0 bytes
2 Dir(s) 34,641,420,288 bytes free
C:\>attrib -s -h Windupdt/*
C:\>dir Windupdt
Volume in drive C has no label.
Directory of C:\Windupdt
06/15/2012 05:07 PM 650,752 winupdate.exe
1 File(s) 650,752 bytes
Disclaimer: The information contained within this advisory is
supplied "as-is" with no warranties or guarantees of fitness of use
or otherwise. Permission is hereby granted for the redistribution
of this advisory, provided that it is not altered except by
reformatting it, and that due credit is given. Permission is
explicitly given for insertion in vulnerability databases and
similar, provided that due credit is given to the author. The
author is not responsible for any misuse of the information
contained herein and accepts no responsibility for any damage
caused by the use or misuse of this information. The author
prohibits any malicious use of security related information or
exploits by the author or elsewhere. Do not attempt to download
Malware samples. The author of this website takes no responsibility
for any kind of damages occurring from improper Malware handling or
the downloading of ANY Malware mentioned on this website or
elsewhere. All content Copyright (c) Malvuln.com (TM).

