The following code is for security research and authorized testing only.
python
#!/usr/bin/env python3
"""
PoC for CVE-2026-0390 (Conceptual)
Demonstrates how untrusted input could theoretically be injected into the boot process.
"""
import subprocess
def exploit_simulation():
# Simulate the attacker having local high privileges
print("[+] Attacker has local high privileges (PR:H)")
# Simulate modifying boot configuration to inject untrusted input
# In a real scenario, this involves low-level disk access or UEFI variable modification.
print("[+] Modifying Boot Configuration Data (BCD)...")
# The vulnerability lies in the loader accepting this input without proper validation
malicious_input = "bypass_security_check_payload"
print(f"[+] Injecting untrusted input: {malicious_input}")
# Trigger the boot loader logic
print("[*] Triggering Windows Boot Loader...")
print("[!] Security decision based on untrusted input.")
print("[!] Security feature bypassed successfully.")
if __name__ == "__main__":
exploit_simulation()