CVE-2023-1902 : Vulnerability Insights and Analysis

This is a detailed overview of CVE-2023-1902 focusing on understanding the vulnerability, its impact, technical details, and mitigation strategies.

Understanding CVE-2023-1902

CVE-2023-1902 is a vulnerability related to the bluetooth HCI host layer logic that may allow a malicious HCI Controller to exploit a dangling reference in the host layer, potentially leading to a crash (DoS) or even remote code execution (RCE) on the Host layer.

What is CVE-2023-1902?

The vulnerability arises from the bluetooth HCI host layer logic failing to clear a global reference to a state pointer after handling connection events. This oversight can be exploited by a malicious HCI Controller to trigger the use of a dangling reference in the host layer, opening up possibilities for a denial of service (DoS) attack or potential remote code execution on the Host layer.

The Impact of CVE-2023-1902

With a CVSS base score of 5.9 (Medium severity), this vulnerability has a high attack complexity, relies on an adjacent network attack vector, and can have a significant availability impact. While the confidentiality and integrity impacts are low, the potential for a DoS or RCE scenario is concerning, especially for affected systems.

Technical Details of CVE-2023-1902

The vulnerability in the bluetooth HCI host layer logic could be exploited by a malicious actor through a series of steps involving connection events, ultimately leading to a crash or potential RCE on the Host layer.

Vulnerability Description

The issue lies in the failure to clear a global reference to a state pointer after handling connection events, allowing for the exploitation of a dangling reference in the host layer.

Affected Systems and Versions

The vulnerability affects Zephyr versions up to 3.3 with a specific condition in the bluetooth HCI host layer logic, making systems running these versions potentially vulnerable to exploitation by a malicious HCI Controller.

Exploitation Mechanism

By manipulating connection events and exploiting the dangling reference in the host layer, an attacker could trigger a crash (DoS) or potentially achieve remote code execution on the Host layer, highlighting the critical nature of this vulnerability.

Mitigation and Prevention

To address CVE-2023-1902 and reduce the risk of exploitation, it is crucial to follow immediate steps and implement long-term security practices to enhance the overall security posture of affected systems.

Immediate Steps to Take

Update to the latest patched version of Zephyr to eliminate the vulnerability and protect systems from potential exploitation.
Monitor network traffic and system logs for any suspicious activity that could indicate an attempted attack leveraging this vulnerability.

Long-Term Security Practices

Regularly scan and assess systems for vulnerabilities, ensuring timely patching and updates to mitigate known security risks.
Implement network segmentation and access controls to limit exposure and contain potential threats within the network.

Patching and Updates

Stay informed about security advisories and updates from ZephyrProject-RTOS to promptly apply patches that address CVE-2023-1902 and other vulnerabilities, safeguarding systems against potential exploits.