Discovery / credits: Malvuln (John Page aka hyp3rlinx) (c) 2024 Original source: https://malvuln.com/advisory/2337b9a12ecf50b94fc95e6ac34b3ecc.txt Contact: malvuln13@gmail.com Media: twitter.com/malvuln Threat: Backdoor.Win32.AsyncRat Vulnerability: Arbitrary Code Execution Description: The malware looks for and executes a x32-bit "CRYPTSP.dll" PE file in its current directory. Therefore, we can hijack the DLL and execute our own code to intercept and terminate the malware. Once loaded the exploit dll will check if the current directory is "C:\Windows\System32", if not we grab our process ID and terminate. Leverage RansomLord v3 for DLL generation, while written as a proof-of-concept to specifically defeat ransomware, it can also be used to generate DLLs to try an exploit other types of malwares. All basic tests were conducted successfully in a virtual machine environment. Family: AsyncRat Type: PE32 MD5: 2337b9a12ecf50b94fc95e6ac34b3ecc SHA256: 3c703ecb3e8c54e352ff39fadbe789bb2313f848bd69551b07bf2ed0a58744b9 Vuln ID: MVID-2024-0683 Disclosure: 05/14/2024 Exploit/PoC: 1) Download RansomLord v3 https://github.com/malvuln/RansomLord 2) Locate the x32 CRYPTSP.dll entry using the -m flag (DLL Map) 3) Use -g flag (Generate Exploit) to output an x32 DLL CRYPTSP.dll, based on an existing vulnerable malware in the victims list. 4) (Optional) -e flag to setup Windows event IOC logging in the registry, this will log the SHA256 hash, full path and filename. 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).