CVE-2024-48887: Fortinet FortiSwitch Auth Bypass Flaw

CVE-2024-48887 Overview

CVE-2024-48887 is an unverified password change vulnerability affecting the Fortinet FortiSwitch GUI. This authentication bypass flaw allows a remote unauthenticated attacker to change administrator passwords via a specially crafted request. The vulnerability stems from improper verification of password change requests, enabling attackers to bypass authentication controls entirely and gain administrative access to affected network switches.

Critical Impact

Remote unauthenticated attackers can change admin passwords without any prior authentication, leading to complete device compromise and potential network-wide security breaches.

Affected Products

• Fortinet FortiSwitch 7.6.0
• Fortinet FortiSwitch versions across multiple release branches (refer to Fortinet Security Advisory FG-IR-24-435 for complete version details)

Discovery Timeline

• 2025-04-08 - CVE-2024-48887 published to NVD
• 2025-07-23 - Last updated in NVD database

Technical Details for CVE-2024-48887

Vulnerability Analysis

This vulnerability is classified under CWE-620 (Unverified Password Change), indicating a fundamental flaw in the authentication flow of the FortiSwitch web management interface. The GUI fails to properly verify the identity of users requesting password changes, allowing unauthenticated remote attackers to modify administrator credentials without presenting valid authentication tokens or the current password.

The attack can be executed remotely over the network without requiring any user interaction, privileges, or prior authentication. An attacker exploiting this vulnerability gains the ability to completely compromise the confidentiality, integrity, and availability of the affected FortiSwitch device. Once administrative credentials are changed, the attacker can lock out legitimate administrators, modify switch configurations, intercept network traffic, or use the compromised device as a pivot point for further network attacks.

Root Cause

The root cause of CVE-2024-48887 lies in insufficient verification mechanisms within the FortiSwitch GUI's password change functionality. The application fails to validate that password change requests originate from authenticated sessions with appropriate authorization. This missing validation allows the password change endpoint to accept and process requests from unauthenticated sources, bypassing the normal authentication flow entirely.

Attack Vector

The attack is executed over the network against the FortiSwitch web management interface. An attacker sends specially crafted HTTP requests to the password change endpoint without first authenticating to the device. The vulnerable endpoint processes these requests as legitimate, allowing the attacker to set a new administrator password of their choosing.

The attack requires network access to the FortiSwitch management interface, which is often exposed on management VLANs or, in misconfigured environments, may be accessible from broader network segments or even the internet. No user interaction is required, making this vulnerability suitable for automated exploitation.

Detection Methods for CVE-2024-48887

Indicators of Compromise

• Unexpected administrator password changes or lockouts from FortiSwitch devices
• Unauthorized configuration changes on FortiSwitch infrastructure
• Unusual HTTP requests to the FortiSwitch web management interface, particularly to password-related endpoints
• Login attempts using newly created or modified administrator accounts

Detection Strategies

• Monitor FortiSwitch audit logs for password change events not associated with legitimate administrative sessions
• Implement network traffic analysis to detect anomalous requests to FortiSwitch management interfaces
• Configure SIEM rules to alert on authentication failures followed by successful access with changed credentials
• Deploy endpoint detection solutions capable of identifying exploitation attempts against network infrastructure

Monitoring Recommendations

• Enable comprehensive logging on all FortiSwitch devices and forward logs to a centralized SIEM platform
• Implement network segmentation monitoring to detect unauthorized access attempts to management interfaces
• Configure alerting for any administrative credential changes outside of approved change windows
• Regularly audit FortiSwitch configurations and user accounts for unauthorized modifications

How to Mitigate CVE-2024-48887

Immediate Actions Required

• Apply the latest security patches from Fortinet immediately to all affected FortiSwitch devices
• Restrict network access to FortiSwitch management interfaces to authorized management networks only
• Review and reset all administrator passwords on potentially affected devices
• Audit FortiSwitch configurations for any unauthorized changes

Patch Information

Fortinet has released security updates to address this vulnerability. Administrators should consult the Fortinet Security Advisory FG-IR-24-435 for specific patch information and upgrade paths for their FortiSwitch firmware versions. Given the critical nature of this vulnerability, immediate patching is strongly recommended.

Workarounds

• Implement strict network access controls to limit management interface access to trusted IP addresses only
• Configure firewall rules to block unauthorized access to FortiSwitch web management ports (typically TCP/443 and TCP/80)
• Enable multi-factor authentication where supported and monitor for bypass attempts
• Consider temporarily disabling the web GUI and using CLI-only management until patches can be applied

# Example: Restrict management access to trusted networks via FortiSwitch CLI
config system interface
    edit "mgmt"
        set allowaccess ping https ssh
        set ip 192.168.1.1 255.255.255.0
        set management-ip 192.168.1.1 255.255.255.0
    next
end
config system admin
    edit "admin"
        set trusthost1 10.0.0.0 255.255.255.0
    next
end