CVE-2026-22572: Fortinet Authentication Bypass Vulnerability

CVE-2026-22572 Overview

CVE-2026-22572 is an authentication bypass vulnerability affecting Fortinet FortiAnalyzer, FortiManager, and FortiManager Cloud products. This vulnerability allows an attacker who already possesses knowledge of an administrator's password to bypass multifactor authentication (MFA) checks by submitting multiple crafted requests through an alternate path or channel. The flaw is classified under CWE-288 (Authentication Bypass Using an Alternate Path or Channel).

Critical Impact

Attackers with stolen admin credentials can completely bypass MFA protections, undermining a critical security control designed to prevent unauthorized access to network management infrastructure.

Affected Products

• Fortinet FortiAnalyzer 7.6.0 through 7.6.3, 7.4.0 through 7.4.7, 7.2.2 through 7.2.11
• Fortinet FortiManager 7.6.0 through 7.6.3, 7.4.0 through 7.4.7, 7.2.2 through 7.2.11
• Fortinet FortiManager Cloud 7.6.0 through 7.6.3, 7.4.0 through 7.4.7, 7.2.2 through 7.2.10

Discovery Timeline

• 2026-03-10 - CVE-2026-22572 published to NVD
• 2026-03-12 - Last updated in NVD database

Technical Details for CVE-2026-22572

Vulnerability Analysis

This vulnerability targets the authentication mechanism in Fortinet's centralized management platforms. The core issue lies in the implementation of multifactor authentication validation, where an alternate authentication path exists that can be exploited to circumvent MFA requirements. By submitting multiple specially crafted requests, an attacker can manipulate the authentication flow to skip the secondary authentication factor entirely.

The affected products serve as critical network management infrastructure components. FortiAnalyzer provides centralized log management and analytics for Fortinet devices, while FortiManager enables centralized management of FortiGate firewalls and other Fortinet devices. Compromising these platforms would give an attacker significant visibility and control over an organization's network security infrastructure.

Root Cause

The vulnerability stems from CWE-288: Authentication Bypass Using an Alternate Path or Channel. The authentication implementation fails to consistently enforce MFA verification across all authentication pathways. Specifically, when multiple crafted requests are submitted in a particular sequence, the system can be tricked into treating the authentication session as having already completed MFA verification, even when the secondary factor has not been validated.

Attack Vector

The attack requires network access to the management interface of the affected Fortinet products. The attacker must first obtain valid administrator credentials through other means (such as phishing, credential stuffing, or previous compromise). With the password in hand, the attacker can then craft a series of requests that exploit the alternate authentication path to bypass MFA checks.

The attack sequence involves:

1. Initiating an authentication session with valid admin credentials
2. Submitting multiple crafted requests designed to manipulate the authentication state
3. Exploiting the alternate path to complete authentication without providing the MFA token
4. Gaining full administrative access to the management platform

Once MFA is bypassed, the attacker gains complete administrative control over the affected management platform, enabling configuration changes, log manipulation, or pivoting to managed devices.

Detection Methods for CVE-2026-22572

Indicators of Compromise

• Multiple rapid authentication attempts from the same source targeting admin accounts
• Authentication sessions that complete without corresponding MFA token validation entries in logs
• Unusual administrative login patterns, especially from unexpected IP addresses or at unusual times
• Discrepancies between authentication logs showing password authentication success and MFA logs showing no token validation

Detection Strategies

• Enable and monitor detailed authentication logging on FortiAnalyzer and FortiManager
• Deploy SIEM correlation rules to detect authentication sessions lacking MFA token validation events
• Implement network monitoring to identify unusual traffic patterns to management interfaces
• Use SentinelOne Singularity to monitor for suspicious authentication behaviors and network anomalies

Monitoring Recommendations

• Review authentication logs regularly for sessions that bypassed expected MFA workflow
• Monitor for multiple rapid-fire requests to authentication endpoints
• Alert on admin logins from new or unexpected IP addresses
• Track authentication flow completeness to ensure both factors are validated

How to Mitigate CVE-2026-22572

Immediate Actions Required

• Restrict network access to FortiAnalyzer and FortiManager management interfaces to trusted IP addresses only
• Review authentication logs for signs of exploitation or suspicious login patterns
• Rotate administrator credentials immediately if compromise is suspected
• Implement additional network-level controls such as VPN requirements for administrative access

Patch Information

Fortinet has released security updates to address this vulnerability. Organizations should consult the Fortinet Security Advisory FG-IR-26-090 for specific version information and upgrade paths. Apply the latest available patches for FortiAnalyzer, FortiManager, and FortiManager Cloud to remediate this vulnerability.

Workarounds

• Implement strict IP-based access controls to limit management interface access to trusted administrative workstations
• Deploy a jump server or bastion host architecture requiring additional authentication before accessing management platforms
• Enable and configure maximum authentication logging to improve detection capabilities
• Consider temporarily disabling remote administrative access until patches can be applied

# Configuration example - Restrict admin access to specific trusted IPs
config system admin
    edit "admin"
        set trusthost1 10.0.0.0 255.255.255.0
        set trusthost2 192.168.1.100 255.255.255.255
    next
end