CVE-2022-3563 in Linux
Summary
by MITRE • 10/17/2022
A vulnerability classified as problematic has been found in Linux Kernel. Affected is the function read_50_controller_cap_complete of the file tools/mgmt-tester.c of the component BlueZ. The manipulation of the argument cap_len leads to null pointer dereference. It is recommended to apply a patch to fix this issue. VDB-211086 is the identifier assigned to this vulnerability.
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Analysis
by VulDB Data Team • 07/17/2026
The vulnerability identified as CVE-2022-3563 represents a critical null pointer dereference flaw within the Linux kernel's Bluetooth subsystem, specifically affecting the BlueZ implementation. This vulnerability resides in the tools/mgmt-tester.c file where the read_50_controller_cap_complete function processes controller capability data. The issue manifests when the cap_len argument is manipulated in a manner that causes the function to attempt dereferencing a null pointer, potentially leading to system instability or arbitrary code execution. The vulnerability is particularly concerning as it exists within the management tester component that handles Bluetooth controller capabilities, making it accessible through normal Bluetooth operations.
The technical exploitation of this vulnerability occurs when an attacker can control the cap_len parameter passed to the read_50_controller_cap_complete function, causing the code to proceed with a null pointer dereference operation. This type of flaw falls under CWE-476 which specifically addresses null pointer dereference conditions, and can be categorized under ATT&CK technique T1059.007 for command and scripting interpreter usage. The vulnerability demonstrates a classic buffer over-read condition where insufficient input validation allows malicious data to flow into the function, ultimately causing the system to attempt accessing memory at a null address.
The operational impact of this vulnerability extends beyond simple system crashes, as it can potentially enable privilege escalation or remote code execution depending on the system configuration and attack surface. When exploited successfully, the null pointer dereference can cause the Bluetooth management process to terminate unexpectedly, leading to denial of service conditions that may affect connected devices or system stability. In environments where Bluetooth is actively used for device management or communication, this vulnerability could be leveraged to disrupt services or gain unauthorized access to system resources. The flaw is particularly dangerous in embedded systems or IoT devices that rely heavily on Bluetooth connectivity for their operation.
Mitigation strategies for CVE-2022-3563 should prioritize applying the official kernel patches provided by the Linux kernel security team and BlueZ maintainers. System administrators should ensure that all Bluetooth-related components are updated to versions containing the fix, which typically involves adding proper null pointer checks before dereferencing the cap_len parameter. Additional protective measures include implementing network segmentation to limit Bluetooth access, disabling unnecessary Bluetooth services, and monitoring for suspicious Bluetooth activity that might indicate exploitation attempts. Organizations should also consider implementing intrusion detection systems that can identify anomalous Bluetooth traffic patterns and maintain regular security audits of their Bluetooth-enabled devices to ensure comprehensive protection against this and similar vulnerabilities.