CVE-2022-39176 in BlueZ
Summary
by MITRE • 09/02/2022
BlueZ before 5.59 allows physically proximate attackers to obtain sensitive information because profiles/audio/avrcp.c does not validate params_len.
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Analysis
by VulDB Data Team • 06/28/2026
The vulnerability identified as CVE-2022-39176 affects BlueZ versions prior to 5.59 and represents a critical information disclosure flaw within the Bluetooth protocol stack implementation. This vulnerability resides in the avrcp.c file within the profiles/audio directory, where insufficient parameter validation creates an attack vector for physically proximate adversaries to extract sensitive information from affected systems.
The technical flaw stems from inadequate validation of the params_len parameter within the Bluetooth AVRCP (Audio Video Remote Control Profile) implementation. When processing incoming Bluetooth commands, the system fails to properly validate the length of parameters passed to the AVRCP profile handlers, allowing attackers to manipulate input data structures. This lack of input sanitization creates a condition where maliciously crafted Bluetooth packets can trigger information leakage through buffer over-read or improper memory access patterns. The vulnerability specifically impacts the Audio Video Remote Control Profile which is commonly used for controlling media playback on Bluetooth devices, making it particularly concerning for consumer electronics and automotive systems.
The operational impact of this vulnerability extends beyond simple information disclosure, as it enables attackers to potentially extract sensitive data from the memory space of affected systems. Physically proximate attackers can exploit this flaw without requiring network access or complex attack chains, making it particularly dangerous in environments where Bluetooth devices are frequently paired or in close proximity to potential attackers. The vulnerability affects various Bluetooth-enabled devices including smartphones, tablets, laptops, automotive infotainment systems, and IoT devices that utilize BlueZ as their Bluetooth stack implementation. Attackers could potentially recover memory contents, session keys, or other sensitive information that might aid in further exploitation attempts.
Mitigation strategies should focus on immediate patch deployment to BlueZ version 5.59 or later, which includes proper parameter validation within the avrcp.c file. System administrators should also implement Bluetooth security best practices including disabling unnecessary Bluetooth services, enforcing strong pairing mechanisms, and regularly auditing Bluetooth device configurations. Network segmentation and monitoring for anomalous Bluetooth traffic patterns can help detect exploitation attempts. From a compliance perspective, this vulnerability aligns with CWE-129 Input Validation and CWE-772 Improper Cleanup, and maps to ATT&CK technique T1046 Network Service Scanning and T1566 Phishing. Organizations should also consider implementing Bluetooth device management policies and ensuring that only trusted devices are paired with critical systems. The vulnerability demonstrates the importance of proper input validation in embedded Bluetooth protocol implementations and highlights the need for thorough security testing of network protocol stacks in IoT and mobile environments.