CVE-2025-22252: Fortinet FortiProxy Auth Bypass Flaw

CVE-2025-22252 Overview

A missing authentication for critical function in Fortinet FortiProxy versions 7.6.0 through 7.6.1, FortiSwitchManager version 7.2.5, and FortiOS versions 7.4.4 through 7.4.6 and version 7.6.0 may allow an attacker with knowledge of an existing admin account to access the device as a valid admin via an authentication bypass.

Critical Impact

This vulnerability could allow unauthorized access to critical system functions, leading to potential data breaches and system compromise.

Affected Products

• Fortinet FortiProxy
• Fortinet FortiSwitchManager
• Fortinet FortiOS

Discovery Timeline

• 2025-05-28 - CVE CVE-2025-22252 published to NVD
• 2025-06-04 - Last updated in NVD database

Technical Details for CVE-2025-22252

Vulnerability Analysis

This vulnerability arises due to inadequate authentication checks on critical functions within the affected Fortinet products. The flaw could be exploited by attackers who have already obtained or guessed the credentials of an existing admin account, allowing them to bypass authentication mechanisms.

Root Cause

The root cause lies in the improper implementation of authentication checks across critical interfaces, particularly affecting administrative functions.

Attack Vector

The attack vector is network-based, allowing attackers to exploit the vulnerability remotely, provided they have knowledge of valid admin credentials.

# Example exploitation code (sanitized)
def exploit_admin_bypass(url, admin_user):
    """Exploits the authentication bypass vulnerability."""
    try:
        session = requests.Session()
        # Bypasses login assuming valid admin credentials
        response = session.get(f"{url}/admin_panel?user={admin_user}")
        if response.ok:
            print("Access granted to admin panel!")
        else:
            print("Failed to exploit.")
    except Exception as ex:
        print(f"Error during exploitation: {ex}")

Detection Methods for CVE-2025-22252

Indicators of Compromise

• Unauthorized access logs
• Unrecognized admin sessions
• Configuration changes without known authorization

Detection Strategies

Utilize SIEM solutions to monitor for unusual access patterns and unauthorized login attempts to administrative interfaces.

Monitoring Recommendations

SentinelOne’s advanced AI-driven detection can identify anomalies in admin access, flagging potential unauthorized exploits of this vulnerability.

How to Mitigate CVE-2025-22252

Immediate Actions Required

• Update FortiProxy to versions later than 7.6.1
• Implement multi-factor authentication for admin accounts
• Regularly audit admin account credentials and access logs

Patch Information

Patches for Fortinet products can be obtained from their official advisory. Ensure all systems are updated promptly.

Workarounds

As an immediate workaround, restrict access to administrative interfaces through network ACLs and increase monitoring of admin activities.

# Configuration example
echo "Restricting admin access to local subnet"
iptables -A INPUT -s 192.168.1.0/24 -p tcp --dport 443 -j ACCEPT
iptables -A INPUT -p tcp --dport 443 -j DROP