lists.openwall.net   lists  /  announce  owl-users  owl-dev  john-users  john-dev  passwdqc-users  yescrypt  popa3d-users  /  oss-security  kernel-hardening  musl  sabotage  tlsify  passwords  /  crypt-dev  xvendor  /  Bugtraq  Full-Disclosure  linux-kernel  linux-netdev  linux-ext4  linux-hardening  PHC 
Open Source and information security mailing list archives
 
Hash Suite for Android: free password hash cracker in your pocket
[<prev] [next>] [day] [month] [year] [list]
Date: Mon, 19 Sep 2022 20:24:33 -0400
From: malvuln <malvuln13@...il.com>
To: fulldisclosure@...lists.org
Subject: [FD] Trojan.Ransom.Ryuk.A / Arbitrary Code Execution

Discovery / credits: Malvuln (John Page aka hyp3rlinx) (c) 2022
Original source:
https://malvuln.com/advisory/5ac0f050f93f86e69026faea1fbb4450.txt
Contact: malvuln13@...il.com
Media: twitter.com/malvuln

Threat: Trojan.Ransom.Ryuk.A
Vulnerability: Arbitrary Code Execution
Description: The ransomware looks for and executes DLLs in its current
directory. Therefore, we can potentially hijack a vuln DLL execute our own
code, control and terminate the malware pre-encryption. Once loaded the
exploit dll will check if the current directory is "C:\Windows\System32",
if not we grab our process ID and terminate. All basic tests were conducted
successfully in a virtual machine environment.
Family: Ryuk
Type: PE32
MD5: 5ac0f050f93f86e69026faea1fbb4450
Vuln ID: MVID-2022-0640
Disclosure: 09/19/2022

Exploit/PoC:
1) Compile the following C code as "urlmon.dll"
2) Place the DLL in same directory as the ransomware
3) Optional - Hide it: attrib +s +h "urlmon.dll"
4) Run the malware

#include "windows.h"

//By malvuln
//Purpose: Exploit Ryuk
/** DISCLAIMER:
Author is NOT responsible for any damages whatsoever by using this software
or improper malware
handling. By using this code you assume and accept all risk implied or
otherwise.
**/

//gcc -c urlmon.c -m32
//gcc -shared -o urlmon.dll urlmon.o -m32

BOOL APIENTRY DllMain(HINSTANCE hInst, DWORD reason, LPVOID reserved){
  switch (reason) {
  case DLL_PROCESS_ATTACH:
   MessageBox(NULL, "Ryuk\nPWNED By MALVULN", "Code Exec PoC", MB_OK);
   TCHAR buf[MAX_PATH];
   GetCurrentDirectory(MAX_PATH, TEXT(buf));
   int rc = strcmp("C:\\Windows\\System32", TEXT(buf));
    if(rc != 0){
    HANDLE handle = OpenProcess(PROCESS_TERMINATE, FALSE, getpid());
     if (NULL != handle) {
        TerminateProcess(handle, 0);
       CloseHandle(handle);
     }
   }
    break;
  }
  return TRUE;
}


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).
_______________________________________________
Sent through the Full Disclosure mailing list
https://nmap.org/mailman/listinfo/fulldisclosure
Web Archives & RSS: https://seclists.org/fulldisclosure/

Powered by blists - more mailing lists