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## https://sploitus.com/exploit?id=PACKETSTORM:161747
Discovery / credits: Malvuln - malvuln.com (c) 2021  
Original source: https://malvuln.com/advisory/de613b96174056ef22b42e112d0e61a5.txt  
Contact: malvuln13@gmail.com  
Media: twitter.com/malvuln  
  
Threat: Trojan-Spy.Win32.KeyLogger.qt  
Vulnerability: Insecure Permissions  
Description: KeyLogger.qt creates a hidden insecure dir named "config" under c:\ drive and grants change (C) permissions to the authenticated user group. Standard users can rename "rundll32.exe" dropped by the keylogger to disable it or replace with their own executable. Then wait for a privileged user to logon to the infected machine to potentially escalate privileges.  
Type: PE32  
MD5: de613b96174056ef22b42e112d0e61a5  
Vuln ID: MVID-2021-0124  
Dropped files: rundll32.exe  
Disclosure: 03/10/2021  
  
Exploit/PoC:  
#include "windows.h"  
  
void main(void){  
  
system("attrib -s -h C:\\config\\rundll32.exe");  
system("rename C:\\config\\rundll32.exe 13");  
  
Sleep(1000);  
puts("[+] Disabled by renaming C:\\config\\rundll32.exe to 13 ...\n");  
Sleep(1000);  
  
puts("[+] Trojan-Spy.Win32.KeyLogger.qt PWNED!");  
puts("[+] MD5: de613b96174056ef22b42e112d0e61a5");  
puts("[+] By Malvuln");  
system("pause");  
}  
  
C:\config>cacls \config  
C:\config 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:\config>dir  
Volume in drive C has no label.  
  
Directory of C:\config  
  
File Not Found  
  
C:\config>dir /a  
Volume in drive C has no label.  
  
Directory of C:\config  
  
06/16/2012 12:54 AM 585,778 rundll32.exe  
1 File(s) 585,778 bytes  
  
  
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