CVE-2019-11868 : Security Advisory and Response

SoftEther VPN Server versions 4.29 or older contain a vulnerability in the See.sys function up to version 4.25, allowing unauthorized users to write arbitrary bytes to a specified kernel address.

Understanding CVE-2019-11868

SoftEther VPN Server versions 4.29 or older are affected by a vulnerability that enables users to exploit the See.sys function up to version 4.25.

What is CVE-2019-11868?

The vulnerability in SoftEther VPN Server versions 4.29 or older allows a user to invoke an IOCTL, enabling the specification of any kernel address for writing arbitrary bytes.

The Impact of CVE-2019-11868

This vulnerability could be exploited by unauthorized users to write arbitrary bytes to a specified kernel address, potentially leading to unauthorized access and system compromise.

Technical Details of CVE-2019-11868

SoftEther VPN Server versions 4.29 or older are susceptible to exploitation due to the following details:

Vulnerability Description

The vulnerability in the See.sys function up to version 4.25 allows users to call an IOCTL and write arbitrary bytes to any specified kernel address.

Affected Systems and Versions

Product: SoftEther VPN Server
Vendor: N/A
Versions affected: Up to version 4.25

Exploitation Mechanism

Unauthorized users can exploit this vulnerability by invoking an IOCTL to specify any kernel address for writing arbitrary bytes.

Mitigation and Prevention

To address CVE-2019-11868, consider the following mitigation strategies:

Immediate Steps to Take

Update SoftEther VPN Server to the latest version.
Implement access controls to restrict unauthorized access.

Long-Term Security Practices

Regularly monitor and audit system logs for any suspicious activities.
Conduct security training for users to raise awareness of potential threats.

Patching and Updates

Apply security patches and updates provided by SoftEther VPN Server to fix the vulnerability and enhance system security.