Discovery / credits: Malvuln - (John Page aka hyp3rlinx) (c) 2022 Original source: https://malvuln.com/advisory/6152709e741c4d5a5d793d35817b4c3d.txt Contact: malvuln13@gmail.com Media: twitter.com/malvuln Threat: Trojan-Ransom.Radamant Vulnerability: Code Execution Description: Radamant tries to load a DLL named "PROPSYS.dll" and execute a hidden PE file "DirectX.exe" from the AppData\Roaming directory. Therefore, we can drop our own DLL to intercept and terminate the malware pre-encryption. The exploit dll checks if the current directory is "C:\Windows\System32", if not we grab our process ID and terminate. We do not need to rely on hash signatures or third-party products, the malwares flaw does the work for us. Endpoint protection systems and or antivirus can potentially be killed prior to executing malware, but this method cannot as there's nothing to kill the DLL just lives on disk waiting. From a defensive perspective you can add the DLLs to a specific network share containing important data as a layered approach. All basic tests were conducted successfully in a virtual machine environment. Family: Radamant Type: PE32 MD5: 6152709e741c4d5a5d793d35817b4c3d Vuln ID: MVID-2022-0589 Disclosure: 05/06/2022 Video PoC URL: https://www.youtube.com/watch?v=EToGLoZjR6Q Exploit/PoC: 1) Compile the following C code as "PROPSYS.dll" 32bit 2) Place the DLL in same directory as the ransomware 3) Optional - Hide it: attrib +s +h "PROPSYS.dll" 4) Run the malware #include "windows.h" //By malvuln //Purpose: Exploit Radamant //gcc -c PROPSYS.c -m32 //gcc -shared -o PROPSYS.dll PROPSYS.o -m32 BOOL APIENTRY DllMain(HINSTANCE hInst, DWORD reason, LPVOID reserved){ switch (reason) { case DLL_PROCESS_ATTACH: MessageBox(NULL, "Code Exec", "by malvuln", MB_OK); TCHAR buf[MAX_PATH]; if(GetCurrentDirectory(MAX_PATH, buf)) if(strcmp("C:\\Windows\\System32", buf) != 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).