Discovery / credits: Malvuln - malvuln.com (c) 2021
Original source: https://malvuln.com/advisory/5c644104f96ccad7a8cf324c2e523530.txt
Contact: malvuln13@gmail.com
Media: twitter.com/malvuln
Threat: Backdoor.Win32.DarkKomet.aspl
Vulnerability: Insecure Permissions
Description: The malware creates an insecure dir 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: 5c644104f96ccad7a8cf324c2e523530
Vuln ID: MVID-2021-0320
Dropped files: winupdate.exe
Disclosure: 08/30/2021
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
07/05/2021 11:27 PM 245,760 winupdate.exe
1 File(s) 245,760 bytes
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