CVE-2025-6029: KIA Keyless Entry Auth Bypass Vulnerability

CVE-2025-6029 Overview

CVE-2025-6029 is a critical vulnerability affecting KIA-branded aftermarket generic smart keyless entry systems, primarily distributed in Ecuador. The system uses fixed learning codes—one code to lock the vehicle and another to unlock it—which enables attackers to execute replay attacks. This fundamental cryptographic weakness allows unauthorized access to vehicles equipped with these aftermarket keyless entry systems.

The manufacturer of these aftermarket devices remains unknown at the time of disclosure, though the CVE record will be updated once this information is clarified.

Critical Impact

Attackers within adjacent network range can capture and replay fixed RF codes to gain unauthorized physical access to vehicles, potentially enabling vehicle theft or unauthorized entry without any user interaction required.

Affected Products

• KIA-branded Aftermarket Generic Smart Keyless Entry System (Ecuador distribution)
• Key Fob Transmitters using fixed learning codes
• Vehicles equipped with these aftermarket keyless entry systems

Discovery Timeline

• June 13, 2025 - CVE-2025-6029 published to NVD
• June 16, 2025 - Last updated in NVD database

Technical Details for CVE-2025-6029

Vulnerability Analysis

This vulnerability is classified under CWE-294 (Authentication Bypass by Capture-replay), representing a fundamental flaw in the authentication mechanism of the affected keyless entry systems. The core issue stems from the use of static, non-rolling codes for vehicle lock and unlock functions.

In a properly designed keyless entry system, rolling codes or challenge-response protocols ensure that each transmission is unique and cannot be reused. However, the affected KIA-branded aftermarket systems transmit identical RF signals for each lock or unlock command. An attacker with appropriate RF capture equipment positioned within adjacent network range can record these transmissions and replay them at will.

The attack requires no authentication, no user interaction, and can be executed with low complexity. The impact extends beyond simple confidentiality concerns—successful exploitation grants attackers high-level access to vehicle integrity (unlocking doors) and availability (potentially disabling the locking mechanism).

Root Cause

The root cause is the implementation of fixed learning codes in the key fob transmitter rather than modern rolling code or encrypted challenge-response authentication mechanisms. This design decision prioritizes simplicity and cost reduction over security, leaving a predictable and easily exploitable authentication scheme.

The key fob transmits the same static code sequence each time the lock or unlock button is pressed. Without cryptographic variation or temporal elements, these codes remain valid indefinitely once captured.

Attack Vector

The attack vector is classified as Adjacent Network (AV:A), meaning the attacker must be within RF communication range of the key fob or vehicle receiver. A typical attack scenario involves:

1. The attacker positions themselves within RF range of the target vehicle or key fob
2. Using software-defined radio (SDR) equipment, the attacker monitors the frequency band used by the keyless entry system
3. When the legitimate owner locks or unlocks the vehicle, the attacker captures the transmitted signal
4. The attacker can later replay the captured signal to lock or unlock the vehicle without possession of the original key fob
5. This attack can be repeated indefinitely since the codes never change

For detailed technical analysis of this vulnerability class, see the ASRG Security Advisory and the Revers3Everything exploit analysis.

Detection Methods for CVE-2025-6029

Indicators of Compromise

• Unexpected vehicle unlock or lock events when the legitimate key fob is not in use
• Multiple lock/unlock cycles in rapid succession detected by vehicle systems
• RF interference or unusual signal patterns near the vehicle
• Presence of unknown RF capture devices in proximity to parking areas

Detection Strategies

• Monitor vehicle event logs for lock/unlock patterns inconsistent with owner behavior
• Deploy RF spectrum analyzers in high-security parking facilities to detect capture attempts
• Implement aftermarket vehicle intrusion detection systems that alert on unauthorized entry
• Review security camera footage for individuals using RF equipment near target vehicles

Monitoring Recommendations

• Maintain awareness of aftermarket keyless entry system installations in fleet vehicles
• Regularly audit vehicle access logs where available
• Consider deploying Faraday pouches for key fobs when vehicles are parked in high-risk areas
• Establish baseline patterns for normal vehicle access to identify anomalies

How to Mitigate CVE-2025-6029

Immediate Actions Required

• Remove or disable affected KIA-branded aftermarket keyless entry systems
• Revert to factory OEM keyless entry systems that utilize rolling codes
• Utilize physical steering wheel locks or other mechanical anti-theft devices as supplementary protection
• Store key fobs in signal-blocking pouches when not in use to prevent capture attempts

Patch Information

No firmware patch is currently available for the affected aftermarket keyless entry systems. The fundamental design flaw of using fixed codes cannot be addressed through a software update alone—the hardware would need to support rolling code or encrypted authentication mechanisms.

Vehicle owners should contact their aftermarket keyless entry system installer to inquire about replacement options with systems that implement proper cryptographic authentication. The manufacturer remains unidentified at this time, limiting traditional vendor support channels.

Workarounds

• Replace the affected aftermarket system with an OEM or certified aftermarket solution using rolling codes
• Use additional physical security measures such as steering wheel locks, brake pedal locks, or wheel clamps
• Park vehicles in monitored or secured locations to reduce attack opportunity windows
• Consider installing an aftermarket vehicle alarm system with motion detection capabilities
• Disable the aftermarket keyless entry system entirely and rely on physical keys until a secure replacement is installed

Vehicle owners in Ecuador should be particularly vigilant given the primary distribution of these systems in that region. Organizations managing vehicle fleets should audit their vehicles for aftermarket keyless entry installations and prioritize replacement of vulnerable systems.