CVE-2025-25251: FortiClient Mac Privilege Escalation Flaw

CVE-2025-25251 Overview

An Incorrect Authorization vulnerability [CWE-863] in FortiClient Mac 7.4.0 through 7.4.2, 7.2.0 through 7.2.8, 7.0.0 through 7.0.14 may allow a local attacker to escalate privileges via crafted XPC messages.

Critical Impact

This vulnerability allows privilege escalation which could completely compromise the affected system.

Affected Products

• Fortinet FortiClient Mac 7.4.0 - 7.4.2
• Fortinet FortiClient Mac 7.2.0 - 7.2.8
• Fortinet FortiClient Mac 7.0.0 - 7.0.14

Discovery Timeline

• Not Available - Vulnerability discovered by Not Available
• Not Available - Responsible disclosure to Fortinet
• Not Available - CVE CVE-2025-25251 assigned
• Not Available - Fortinet releases security patch
• 2025-05-28 - CVE CVE-2025-25251 published to NVD
• 2025-06-04 - Last updated in NVD database

Technical Details for CVE-2025-25251

Vulnerability Analysis

The vulnerability stems from an incorrect authorization mechanism in FortiClient Mac which allows crafted XPC messages to escalate privileges from an untrusted user to a privileged context. This can lead to full system compromise, allowing attackers to execute arbitrary commands or modify sensitive files.

Root Cause

Lack of proper validation in the XPC message handling logic results in authorization bypass, enabling local privilege escalation.

Attack Vector

The attacker must have local access to the system to send maliciously crafted XPC messages to FortiClient, thereby gaining elevated privileges.

# Example exploitation code (sanitized)
#!/bin/bash

# XPC message crafting
sendXpcMessage() {
    echo "Crafting and sending malicious XPC message..."
    # Further implementation required based on actual functions
    # This is a placeholder for educational purposes
}

sendXpcMessage

Detection Methods for CVE-2025-25251

Indicators of Compromise

• Unusual privilege escalation activities
• Unexpected modification of critical system files
• Unauthorized execution of privileged commands

Detection Strategies

Utilize process monitoring tools to detect unauthorized execution and privilege escalation attempts. Monitor log files for signs of abnormal activities related to XPC communication.

Monitoring Recommendations

Implement continuous monitoring on sensitive directories and configuration files. Enable auditing and logging for all privilege-related actions and XPC message transactions within the FortiClient application.

How to Mitigate CVE-2025-25251

Immediate Actions Required

• Disable unnecessary XPC services if possible
• Restrict local user account capabilities
• Improve logging to capture anomalous activities

Patch Information

Fortinet has released patches addressing this vulnerability. Users are strongly advised to upgrade to the latest version of FortiClient Mac, following Fortinet’s guidance from their advisory.

Workarounds

Users unable to apply the patch immediately should restrict local user access to trusted users only and monitor XPC service activities closely.

# Configuration example
echo "restricting user access"
sudo chown -R root:wheel /Applications/FortiClient.app/
sudo chmod -R 700 /Applications/FortiClient.app/