CVE-2025-32061: Bluetooth Stack Buffer Overflow RCE Flaw

CVE-2025-32061 Overview

CVE-2025-32061 is a stack-based buffer overflow vulnerability in the Bluetooth stack developed by Alps Alpine, integrated within the Infotainment ECU manufactured by Bosch. The flaw stems from improper boundary validation of user-supplied data, allowing an attacker within Bluetooth range to trigger a buffer overflow by sending a specially crafted packet on an established L2CAP (Logical Link Control and Adaptation Protocol) channel. Successful exploitation enables remote code execution with root privileges on the Infotainment ECU, presenting a significant risk to vehicle security and safety.

This vulnerability was first identified on the Nissan Leaf ZE1 manufactured in 2020, affecting the vehicle's infotainment system and potentially exposing connected vehicle functions to unauthorized control.

Critical Impact

Remote code execution with root privileges on the vehicle's Infotainment ECU via adjacent network Bluetooth attack, potentially compromising vehicle safety systems.

Affected Products

• Bosch Infotainment ECU with Alps Alpine Bluetooth stack
• Nissan Leaf ZE1 (2020 model year)
• Vehicles utilizing affected Bosch Infotainment ECU components

Discovery Timeline

• 2026-02-15 - CVE-2025-32061 published to NVD
• 2026-02-18 - Last updated in NVD database

Technical Details for CVE-2025-32061

Vulnerability Analysis

This vulnerability (CWE-121: Stack-based Buffer Overflow) affects the Bluetooth communication layer of the Bosch Infotainment ECU. The flaw resides specifically within the L2CAP channel handling routines developed by Alps Alpine. When the infotainment system processes incoming Bluetooth packets, insufficient boundary validation allows an attacker to overflow a stack buffer by transmitting malformed data over an established L2CAP connection.

The exploitation scenario requires the attacker to be within Bluetooth range (approximately 10-100 meters depending on the Bluetooth class) of the target vehicle. Once in range, the attacker can establish a Bluetooth connection and send crafted packets that exceed expected buffer boundaries, leading to stack corruption and ultimately arbitrary code execution with root-level privileges on the ECU.

For detailed technical analysis, refer to the Black Hat Presentation Paper and the PCA Cybersecurity Advisory.

Root Cause

The root cause of CVE-2025-32061 is improper input validation within the Bluetooth stack's L2CAP packet processing routine. The vulnerable code fails to verify that incoming data fits within allocated stack buffer boundaries before copying it, resulting in a classic stack-based buffer overflow condition. This type of vulnerability typically occurs when:

• Length fields in network packets are not validated against buffer sizes
• Fixed-size stack buffers receive variable-length user input without bounds checking
• Memory copy operations do not verify destination buffer capacity

Attack Vector

The attack vector for this vulnerability is Adjacent Network, meaning the attacker must be within Bluetooth range of the target vehicle. The exploitation process involves:

1. Proximity: Attacker positions themselves within Bluetooth communication range of the target vehicle
2. Connection Establishment: Attacker initiates Bluetooth pairing or connects to an existing L2CAP channel
3. Payload Delivery: Malicious packet containing overflow payload is transmitted over the L2CAP channel
4. Stack Corruption: The oversized data overwrites critical stack memory including return addresses
5. Code Execution: Attacker-controlled shellcode executes with root privileges on the Infotainment ECU

The vulnerability requires no authentication or user interaction, making it particularly dangerous in scenarios where vehicles are parked in public areas or attackers can follow target vehicles.

Detection Methods for CVE-2025-32061

Indicators of Compromise

• Unexpected Bluetooth connection attempts or pairings logged by the infotainment system
• Anomalous L2CAP packet sizes or malformed Bluetooth traffic in vehicle network logs
• Unusual process behavior or unexpected root-level processes on the Infotainment ECU
• Modified system files or configurations on the infotainment system
• Crash logs or system reboots associated with Bluetooth stack failures

Detection Strategies

• Monitor vehicle CAN bus traffic for anomalous commands originating from the Infotainment ECU
• Implement Bluetooth traffic analysis tools during vehicle security assessments
• Review infotainment system logs for Bluetooth stack crashes or segmentation faults
• Deploy intrusion detection systems capable of analyzing in-vehicle network traffic
• Perform periodic security audits of Bluetooth-enabled vehicle components

Monitoring Recommendations

• Enable comprehensive logging on vehicle infotainment systems where supported
• Implement network segmentation between infotainment and critical vehicle control systems
• Consider aftermarket security solutions that monitor CAN bus communications
• Establish baseline Bluetooth behavior patterns for anomaly detection
• Work with vehicle manufacturers to obtain security update notifications

How to Mitigate CVE-2025-32061

Immediate Actions Required

• Contact Nissan or your vehicle dealer to inquire about available firmware updates for the Infotainment ECU
• Disable Bluetooth functionality on the infotainment system if not required for vehicle operation
• Avoid parking in areas where prolonged Bluetooth attacks could be conducted
• Monitor for official security advisories from Bosch and Nissan regarding this vulnerability
• Consider professional security assessment for fleet vehicles potentially affected

Patch Information

Vehicle owners should contact their Nissan dealer or authorized service center to determine if a security patch is available for their specific vehicle model. Firmware updates for the Bosch Infotainment ECU would need to be applied by authorized technicians with access to the vehicle's diagnostic systems.

Additional technical details are available in the PCA Cybersecurity Advisory.

Workarounds

• Disable Bluetooth on the vehicle's infotainment system through the settings menu when not in active use
• Avoid accepting unknown Bluetooth pairing requests
• Park vehicles in secure locations to reduce exposure to proximity-based attacks
• Monitor official Nissan and Bosch channels for security updates
• Consider physical disconnection of Bluetooth modules if the risk profile warrants it (consult authorized technicians)

# Recommended: Check with your dealer for firmware version
# Ensure your infotainment system is running the latest available firmware
# Disable Bluetooth via: Settings > Bluetooth > Off
# Note: Actual mitigation requires manufacturer-provided firmware updates