The following code is for security research and authorized testing only.
python
/*
* PoC for CVE-2026-33840 (Windows Win32k Use-After-Free)
* This is a conceptual demonstration of triggering the UAF vulnerability.
* Do not use for malicious purposes.
*/
#include <windows.h>
#include <stdio.h>
// Simulating the trigger for the ICOMP UAF
void TriggerUAF() {
HWND hWnd = CreateWindowExW(0, L"BUTTON", L"PoC", 0, 0, 0, 0, 0, NULL, NULL, NULL, NULL);
if (!hWnd) {
printf("Failed to create window.\n");
return;
}
// Step 1: Trigger the object allocation in Win32k
// (Specific API calls omitted for safety)
// Step 2: Trigger the free operation via specific message sequence
// SendMessage(hWnd, WM_XXX, ...);
// Step 3: Attempt to use the freed object (Use-After-Free)
// This causes the kernel to access invalid memory
// SendMessage(hWnd, WM_YYY, ...);
printf("Trigger sent. If vulnerable, system may crash or execute code.\n");
}
int main() {
printf("Starting PoC for CVE-2026-33840...\n");
TriggerUAF();
return 0;
}