CVE-2023-39075 Overview
CVE-2023-39075 is a denial of service vulnerability affecting the automotive infotainment system in the Renault Zoe EV 2021. The vulnerability allows attackers with physical access to crash the infotainment system by sending arbitrary USB data via a connected USB device. This affects firmware versions 283C35202R to 283C35519R (builds from 11.10.2021 to 16.01.2023).
Critical Impact
Attackers with physical access to the vehicle's USB port can trigger a denial of service condition, crashing the infotainment system and potentially disrupting driver information and entertainment functions.
Affected Products
- Renault Zoe EV 2021 Firmware versions 283C35202R to 283C35519R
- Renault Zoe EV 2021 Hardware
- Builds from 11.10.2021 to 16.01.2023
Discovery Timeline
- August 3, 2023 - CVE-2023-39075 published to NVD
- November 21, 2024 - Last updated in NVD database
Technical Details for CVE-2023-39075
Vulnerability Analysis
This vulnerability exists in the Renault Zoe EV 2021 infotainment system's USB input handling functionality. The system fails to properly validate or sanitize USB data received from connected devices, allowing malformed or unexpected USB packets to cause the infotainment system to crash. This represents a firmware vulnerability in an embedded automotive system.
The attack requires physical access to the vehicle's USB port, limiting the attack surface to scenarios where an attacker can directly connect a malicious USB device. However, once connected, the arbitrary USB data transmission can reliably trigger the denial of service condition without requiring any user interaction or authentication.
Root Cause
The root cause of this vulnerability is improper input validation in the infotainment system's USB data processing routines. The firmware does not adequately sanitize or validate incoming USB data streams, making it susceptible to crashes when processing unexpected or malformed input. This type of vulnerability is commonly discovered through USB fuzzing techniques, where random or crafted USB packets are sent to identify parsing weaknesses.
Attack Vector
The attack vector for CVE-2023-39075 requires physical access to the vehicle. An attacker must connect a USB device capable of transmitting arbitrary data to one of the vehicle's USB ports. The malicious device then sends crafted USB packets that exploit the input validation weakness, causing the infotainment system to crash.
The attack process involves:
- Physical access to the Renault Zoe EV 2021 USB port
- Connection of a malicious USB device (such as a Raspberry Pi or similar programmable device)
- Transmission of arbitrary or fuzzed USB data packets
- Triggering of the denial of service condition in the infotainment system
Technical details on automotive USB fuzzing techniques can be found in the DH Jeong Fuzzing Guide.
Detection Methods for CVE-2023-39075
Indicators of Compromise
- Unexpected infotainment system crashes or reboots after USB device connection
- Unknown or unauthorized USB devices found connected to vehicle ports
- Repeated infotainment system instability when USB devices are present
- Log entries indicating USB subsystem errors or exceptions (if accessible)
Detection Strategies
- Monitor for unexpected infotainment system restarts or crashes
- Implement USB device whitelisting if supported by the firmware
- Conduct periodic inspections of vehicle USB ports for unauthorized devices
- Review vehicle diagnostic logs for USB-related anomalies
Monitoring Recommendations
- Enable and preserve infotainment system crash logs for forensic analysis
- Document baseline infotainment system behavior for comparison
- Consider physical security measures for vehicle access points
- Report unusual infotainment behavior to Renault service centers
How to Mitigate CVE-2023-39075
Immediate Actions Required
- Avoid connecting unknown or untrusted USB devices to the vehicle
- Physically inspect USB ports before vehicle operation
- Maintain physical security of the vehicle to prevent unauthorized access
- Contact Renault dealership to inquire about available firmware updates
- Monitor Renault security advisories for patches addressing this vulnerability
Patch Information
No official vendor advisory or patch information is currently available in the CVE data. Vehicle owners should contact their local Renault dealership or authorized service center to inquire about firmware updates that address this vulnerability. Firmware updates for automotive infotainment systems typically require service center installation.
For additional technical details, refer to the NIST CVE-2023-39075 Details and the original vulnerability disclosure at DH Jeong Renault Zoe Vulnerability.
Workarounds
- Only connect trusted USB devices such as charging cables from known manufacturers
- Disable USB media playback functionality if the option is available in system settings
- Use physical USB port covers or blockers when ports are not in use
- Maintain awareness of physical access to the vehicle
- Consider using Bluetooth or other wireless connectivity options instead of USB when possible
Disclaimer: This content was generated using AI. While we strive for accuracy, please verify critical information with official sources.
