CVE-2023-24821 Explained : Impact and Mitigation

This CVE record pertains to a vulnerability in RIOT-OS that allows for an Integer Underflow during defragmentation, potentially leading to out-of-bounds write attacks.

Understanding CVE-2023-24821

This section delves into the details of CVE-2023-24821, shedding light on the vulnerability's nature and impact.

What is CVE-2023-24821?

CVE-2023-24821 is a security flaw found in RIOT-OS, an operating system designed to support Internet of Things (IoT) devices. The vulnerability exists in the network stack of RIOT-OS, specifically in its ability to process 6LoWPAN frames. Prior to version 2022.10, attackers could exploit this flaw by sending a specially crafted frame to the device, resulting in a significant out-of-bounds write operation extending beyond the packet buffer. This write operation triggers a hard fault exception upon reaching the last page of RAM, causing the system to become unresponsive until a reset is performed. The primary impact of this vulnerability is denial of service (DoS). The issue has been addressed in version 2022.10.

The Impact of CVE-2023-24821

The impact of CVE-2023-24821 is deemed high, with a CVSS v3.1 base severity score of 7.5. The vulnerability can result in a denial of service condition, making affected devices unresponsive until manually reset.

Technical Details of CVE-2023-24821

This section provides more technical insights into the vulnerability, including its description, affected systems, and the exploitation mechanism.

Vulnerability Description

The vulnerability in RIOT-OS allows for an Integer Underflow during defragmentation, leading to out-of-bounds write attacks. Attackers can exploit this flaw to trigger a hard fault exception within the system, causing it to halt and necessitate a manual reset.

Affected Systems and Versions

The affected product is RIOT running versions prior to 2022.10. Devices using RIOT-OS with these versions are susceptible to the Integer Underflow vulnerability during defragmentation.

Exploitation Mechanism

To exploit this vulnerability, attackers send specially crafted packets to the target device, triggering the out-of-bounds write operation and subsequently causing a hard fault exception that renders the device unresponsive.

Mitigation and Prevention

In this section, we discuss the steps that can be taken to mitigate the risks posed by CVE-2023-24821 and prevent potential exploitation.

Immediate Steps to Take

To mitigate the risk associated with CVE-2023-24821, it is recommended to update RIOT-OS to version 2022.10 or later, which includes the necessary patches to address the vulnerability. Additionally, disabling support for fragmented IP datagrams can serve as a temporary workaround until the system is fully updated.

Long-Term Security Practices

In the long term, it is crucial for organizations and users to prioritize timely software updates and security patches to address known vulnerabilities promptly. Implementing robust security measures and conducting regular security assessments can also help enhance the overall resilience of IoT devices.

Patching and Updates

Ensuring that RIOT-OS is regularly updated with the latest security patches and versions is essential to prevent the exploitation of vulnerabilities like CVE-2023-24821. Organizations should have a structured patch management process in place to promptly deploy updates and protect against emerging threats.