CVE-2023-5748 : Security Advisory and Response

This article provides detailed information about CVE-2023-5748, its impact, technical details, and mitigation strategies.

Understanding CVE-2023-5748

CVE-2023-5748 is a vulnerability found in the Synology SSL VPN Client, allowing local users to conduct denial-of-service attacks through a buffer copy without checking the size of input.

What is CVE-2023-5748?

The vulnerability identified as CVE-2023-5748 involves a buffer copy without checking the size of input, also known as a 'Classic Buffer Overflow' issue. It exists in the Common Gateway Interface (CGI) component of Synology SSL VPN Client versions prior to 1.4.7-0687.

The Impact of CVE-2023-5748

The impact of CVE-2023-5748 is categorized as LOW severity based on the Common Vulnerability Scoring System (CVSS) version 3.1. It allows local users to execute denial-of-service attacks, affecting the availability of the system.

Technical Details of CVE-2023-5748

The following technical aspects provide a deeper insight into the CVE-2023-5748 vulnerability:

Vulnerability Description

The vulnerability allows local users to exploit the buffer copy without checking the size of input, leading to denial-of-service attacks through unspecified vectors.

Affected Systems and Versions

Vendor: Synology
Product: Synology SSL VPN Client
Affected Versions: All versions before 1.4.7-0687
Status: Affected

Exploitation Mechanism

The vulnerability arises from inadequate size checking of input buffers within the CGI component of the Synology SSL VPN Client, enabling local users to manipulate data and trigger denial-of-service conditions.

Mitigation and Prevention

To safeguard systems from CVE-2023-5748, the following mitigation and prevention strategies are recommended:

Immediate Steps to Take

Update to the latest version of the Synology SSL VPN Client (1.4.7-0687) to mitigate the vulnerability.
Ensure that access to the affected system is restricted to trusted users only.

Long-Term Security Practices

Regularly monitor and apply security patches provided by Synology for the SSL VPN Client.
Implement network segmentation to minimize the impact of potential attacks.

Patching and Updates

Synology has released updates to address the vulnerability in the SSL VPN Client. It is crucial for users to promptly install these patches to enhance the security posture of their systems.