CVE-2025-26168: Critical Local Privilege Escalation Vulnerability in IXON VPN Client

Overview

In today’s cybersecurity environment, vulnerabilities are a significant concern, and the recent discovery of the CVE-2025-26168 vulnerability in the IXON VPN Client amplifies this concern. This critical security flaw affects versions of the IXON VPN Client before 1.4.4 on Linux and macOS. The vulnerability is of high significance as it allows local privilege escalation to root, leading to potential system compromise or data leakage. Given the severity of this vulnerability and its potential impact on the integrity of systems and data, it’s imperative for all stakeholders to gain an understanding of it and implement the necessary mitigation measures.

Vulnerability Summary

CVE ID: CVE-2025-26168
Severity: Critical (8.1 CVSS Score)
Attack Vector: Local
Privileges Required: Low
User Interaction: Required
Impact: Potential system compromise or data leakage

Affected Products

Product | Affected Versions

IXON VPN Client | Before 1.4.4 on Linux and macOS

How the Exploit Works

The CVE-2025-26168 vulnerability in the IXON VPN Client arises from the software’s inappropriate handling of a configuration file that can be manipulated by a low-privileged user. Specifically, there’s a race condition whereby a temporary configuration file, stored in a directory that is world-writable, can be overwritten. This allows for local privilege escalation to root, enabling the attacker to execute code with the highest level of privileges on the system, potentially leading to full system compromise.

Conceptual Example Code

Below is a conceptual example of how the vulnerability might be exploited using a shell command:

# Gain low-level user access
$ ssh lowprivilegeduser@target.example.com
# Navigate to the world-writable directory
$ cd /path/to/worldwritable/directory
# Overwrite the temporary configuration file
$ echo "malicious code" > temp_config_file
# Wait for the IXON VPN Client to execute the malicious code

In this example, the attacker first gains low-level user access to the target system. They then navigate to the world-writable directory that contains the temporary configuration file. Next, the attacker overwrites the temporary configuration file with malicious code. Finally, when the IXON VPN Client reads from the temporary configuration file, it unknowingly executes the malicious code, leading to privilege escalation.

Mitigation Measures

It is recommended that all users of the affected IXON VPN Client versions immediately apply the vendor-provided patch to address this vulnerability. If the patch cannot be applied immediately, users should consider using a Web Application Firewall (WAF) or Intrusion Detection System (IDS) as temporary mitigation. However, these measures should not be considered a long-term solution as they only help to reduce the risk of exploitation, not eliminate it entirely.