An issue was discovered in the Hyundai Gen5W_L in-vehicle infotainment system AE_E_PE_EUR.S5W_L001.001.211214. The decryption binary used to decrypt firmware files has an information leak that allows an attacker to read the AES key and initialization vector from memory. An attacker may exploit this to create custom firmware that may be installed in the IVI system. Then, an attacker may be able to install a backdoor in the IVI system that may allow him to control it, if it is connected to the Internet through Wi-Fi.