Discovery / credits: Malvuln - malvuln.com (c) 2021 Original source: https://malvuln.com/advisory/21cd8bab6b3569f7b375a69a37e36c50.txt Contact: malvuln13@gmail.com Media: twitter.com/malvuln Threat: Trojan.Win32.SecondThought.ak Vulnerability: Insecure Permissions Description: The malware creates a dir with insecure permissions under c:\ drive and grants change (C) permissions to the authenticated user group. Standard users can rename the executable 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: 21cd8bab6b3569f7b375a69a37e36c50 Vuln ID: MVID-2021-0257 Dropped files: install113.exe Disclosure: 06/23/2021 Exploit/PoC: C:\>cacls temporary C:\temporary 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 temporary Volume in drive C has no label. Directory of C:\temporary 06/16/2021 02:51 AM 0 install113.exe 1 File(s) 0 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).