Securing your connected car from hackers requires a layered defense approach: keeping your vehicle’s software updated, securing your key fob from relay attacks, disabling unnecessary connectivity features, using strong passwords on companion apps, and being cautious about third-party devices plugged into your OBD-II port. These measures address the primary attack vectors that security researchers have demonstrated over the years, from remote exploitation of cellular connections to physical access through diagnostic ports. The reality is that modern vehicles contain dozens of electronic control units networked together, and any connected component””from infotainment systems to telematics modules””can potentially serve as an entry point. Consider the 2015 Jeep Cherokee demonstration by researchers Charlie Miller and Chris Valasek, which remains one of the most cited examples in automotive cybersecurity.
They remotely accessed a vehicle through its Uconnect infotainment system, eventually gaining control of steering and braking while the vehicle was in motion. That research prompted a 1.4 million vehicle recall and fundamentally changed how the automotive industry approaches cybersecurity. While manufacturers have since implemented more robust protections, the attack surface continues to expand as vehicles gain more connected features. This article covers the specific vulnerabilities in modern vehicles, practical steps for protection, the limitations of current security measures, and what to watch for as automotive technology evolves.
Table of Contents
- What Makes Connected Cars Vulnerable to Hackers?
- Securing Your Vehicle’s Software and Firmware Against Intrusion
- Protecting Your Key Fob From Relay and Cloning Attacks
- Third-Party Devices and Your OBD-II Port: Understanding the Risks
- Smartphone Apps and Connected Services: Securing Remote Access
- Vehicle Telematics and Manufacturer Data Collection
- The Future of Automotive Cybersecurity
- Conclusion
What Makes Connected Cars Vulnerable to Hackers?
Modern vehicles are essentially computers on wheels, containing upwards of 100 million lines of code in some cases””more than a modern fighter jet. This complexity creates numerous potential entry points. The primary attack surfaces include cellular telematics units that enable remote features like stolen vehicle tracking and remote start, Bluetooth and WiFi connections for device pairing, USB ports that could accept malicious devices, OBD-II diagnostic ports that provide deep access to vehicle systems, and companion smartphone apps that may store credentials insecurely. The architecture of vehicle networks compounds these risks. Most cars use a Controller Area Network (CAN bus) protocol that was designed in the 1980s for reliability, not security. CAN bus lacks authentication””any electronic control unit on the network can send commands to any other unit without proving its identity.
This means that once an attacker gains access to the network through any connected component, they can potentially send commands to safety-critical systems. Security researchers have historically demonstrated attacks ranging from disabling brakes to manipulating speedometer readings. However, the difficulty of exploiting these vulnerabilities varies enormously. Remote attacks through cellular connections require sophisticated capabilities and deep knowledge of specific manufacturer systems. Physical attacks through the OBD-II port are much simpler but require access to the vehicle’s interior. When evaluating your risk, consider that most real-world car theft still relies on traditional methods or key fob relay attacks rather than sophisticated software exploits.
Securing Your Vehicle’s Software and Firmware Against Intrusion
The most critical security measure is ensuring your vehicle runs current software. Manufacturers regularly release updates that patch discovered vulnerabilities, though the update process varies significantly between brands. Some vehicles receive over-the-air updates automatically, similar to smartphones, while others require dealer visits for critical security patches. check your owner’s manual or manufacturer’s website to understand your vehicle’s update mechanism, and verify that automatic updates are enabled if available. Tesla pioneered over-the-air updates in vehicles and has used this capability to rapidly deploy security fixes, sometimes within days of vulnerability disclosure.
Traditional manufacturers have been slower to adopt this technology, though most new vehicles from major brands now support at least some wireless updating capability. If your vehicle requires dealer service for updates, be aware that many owners skip these visits if the vehicle appears to function normally, leaving known vulnerabilities unpatched for years. One limitation worth noting: even with current software, your vehicle may contain components from third-party suppliers that receive updates on different schedules or not at all. Infotainment systems, in particular, often run on supplier-provided platforms that may have different security lifecycles than the vehicle itself. There is no consumer-accessible way to audit these components, which represents a significant gap in current automotive security transparency.
Protecting Your Key Fob From Relay and Cloning Attacks
Key fob vulnerabilities represent one of the most practical threats to connected vehicles. Relay attacks work by using two devices: one near your key fob (even through walls) and another near your vehicle. These devices extend the signal range, tricking your car into thinking the key is present and unlocking the doors or enabling ignition. This technique requires no sophisticated hacking””the equipment has been available for purchase online, and the attack can be executed in seconds. Store your key fob in a signal-blocking pouch (often called a Faraday bag) when not in use, particularly at night or when parked in public areas.
Some manufacturers offer key fobs with motion sensors that disable the signal when stationary for several minutes, reducing vulnerability during overnight periods. Check whether your vehicle allows you to disable passive entry entirely, requiring button presses to unlock””this eliminates the relay attack vector at the cost of convenience. Older vehicles may also be vulnerable to key cloning, where attackers capture the rolling code signal and calculate future codes or exploit weak encryption. This was notably demonstrated against vehicles using the Megamos Crypto and DST40 systems. If you own an older vehicle, research whether your specific model uses known-vulnerable key systems. Some owners of high-value classic or collectible vehicles have added aftermarket security systems as an additional layer, though integrating these with modern vehicle electronics can be complex.
Third-Party Devices and Your OBD-II Port: Understanding the Risks
The OBD-II port, typically located under the dashboard, provides direct access to your vehicle’s internal network. Insurance companies, fleet managers, and aftermarket accessories all use devices that plug into this port””from usage-based insurance dongles to performance tuners to diagnostic scanners. Each of these devices represents a potential security risk, either through the device itself or through its network connections. Research has shown vulnerabilities in several aftermarket OBD-II devices, including insurance tracking dongles that could be remotely exploited to access vehicle systems. Before plugging any device into your OBD-II port, research the manufacturer’s security practices.
Ask whether the device has undergone independent security auditing, how it handles data transmission, and whether it receives security updates. Remove devices when not actively needed rather than leaving them permanently installed. Some security-conscious vehicle owners install OBD-II port locks or relocate the port to a less accessible location. These physical security measures prevent casual access but won’t stop a determined attacker with time and tools. The tradeoff is that legitimate mechanics and diagnostic equipment will also need the lock removed or port location disclosed, which adds friction to routine maintenance. For most drivers, simply avoiding unnecessary OBD-II devices and removing them when not in use provides reasonable protection.
Smartphone Apps and Connected Services: Securing Remote Access
Nearly every modern vehicle comes with a companion smartphone app offering features like remote start, lock and unlock, vehicle location, and diagnostic information. These apps authenticate to manufacturer cloud services, which then communicate with your vehicle. Compromise of your app credentials means an attacker gains these same capabilities””locating your vehicle, unlocking it, and in some cases starting the engine. Treat your vehicle app account with the same seriousness as your banking credentials. Use a strong, unique password and enable two-factor authentication if available.
Be aware that some vehicle apps have historically had security weaknesses””research has found issues ranging from insecure API endpoints to inadequate session management. Monitor your account for unauthorized access and review the app’s permission requests critically. There’s rarely a legitimate reason for a vehicle app to access your contacts or photos. When selling a vehicle, thoroughly disconnect it from your account through both the app and manufacturer website. Some owners have discovered that previous owner accounts remained linked, potentially granting ongoing access to vehicle location and controls. Similarly, if you purchase a used vehicle with connected features, verify through the dealer that all previous owner associations have been removed from the manufacturer’s systems, not just the vehicle’s local memory.
Vehicle Telematics and Manufacturer Data Collection
Beyond security vulnerabilities, connected cars collect substantial data about your driving behavior, locations, and habits. This data typically flows to manufacturer servers, and from there may be shared with insurance companies, data brokers, or law enforcement under various circumstances. While not a hacking risk in the traditional sense, this data collection represents a privacy consideration that overlaps with security.
Review your vehicle’s privacy settings, often found within the infotainment system or companion app. Some manufacturers allow you to opt out of certain data collection, though this may disable connected features. A 2024 privacy study by the Mozilla Foundation rated 25 major car brands on privacy practices, with every brand receiving failing grades””suggesting this is an industry-wide challenge rather than isolated to specific manufacturers. Consider what data you’re comfortable sharing in exchange for connected features, and disable features you don’t actively use.
The Future of Automotive Cybersecurity
The automotive industry has made genuine progress since the early demonstrations that exposed systemic vulnerabilities. Manufacturers have hired dedicated security teams, implemented network segmentation to isolate safety-critical systems, and begun adopting intrusion detection capabilities. Regulatory frameworks like UNECE WP.29, which requires cybersecurity management systems for vehicles sold in many markets, have established baseline requirements.
Looking forward, the expansion of vehicle-to-everything (V2X) communication, increased autonomy features, and deeper cloud integration will continue expanding the attack surface. Security will need to evolve correspondingly. For consumers, this means remaining attentive to manufacturer security reputation when purchasing vehicles, maintaining vigilance about updates and third-party devices, and recognizing that vehicle cybersecurity is an ongoing process rather than a one-time configuration.
Conclusion
Protecting your connected car requires attention to multiple fronts: software updates, key fob security, OBD-II port access, app credentials, and awareness of what data your vehicle collects. No single measure provides complete protection, but layering these defenses significantly reduces your exposure to both targeted attacks and opportunistic criminals using commodity tools for relay attacks or device exploitation.
The good news is that sophisticated remote attacks remain relatively rare in practice, with key fob relay attacks and credential theft representing more common real-world threats. Focus your efforts on practical protections like signal-blocking pouches, strong authentication on apps, and removing unnecessary connected devices. Stay informed about vulnerabilities specific to your vehicle make and model, and don’t hesitate to contact your dealer or manufacturer if you have security concerns about your specific vehicle.