CVE-2025-57823
📋 TL;DR
A forced browsing vulnerability in Fortinet FortiAuthenticator allows authenticated attackers with sponsor permissions to access and download device logs via specific endpoints. This affects FortiAuthenticator versions 6.3 through 6.6.6, potentially exposing sensitive log information to unauthorized users.
💻 Affected Systems
- Fortinet FortiAuthenticator
📦 What is this software?
⚠️ Risk & Real-World Impact
Worst Case
An attacker with sponsor permissions could exfiltrate sensitive log data containing authentication attempts, user activities, and system events, potentially enabling further attacks or exposing confidential information.
Likely Case
An authenticated sponsor-level user accesses and downloads logs they shouldn't have permission to view, potentially exposing sensitive operational data and user activity information.
If Mitigated
With proper access controls and monitoring, the impact is limited to authorized sponsor users accessing logs they shouldn't see, with detection of unusual log access patterns.
🎯 Exploit Status
Exploitation requires authenticated access with sponsor permissions; involves accessing specific endpoints directly.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: FortiAuthenticator 6.6.7 and later
Vendor Advisory: https://fortiguard.fortinet.com/psirt/FG-IR-25-554
Restart Required: Yes
Instructions:
1. Backup current configuration. 2. Download FortiAuthenticator 6.6.7 or later from Fortinet support portal. 3. Upload and install the firmware update via web interface or CLI. 4. Reboot the device after installation completes.
🔧 Temporary Workarounds
Restrict Sponsor Permissions
allReview and minimize sponsor-level user accounts; ensure only necessary users have sponsor permissions.
Network Segmentation
allRestrict network access to FortiAuthenticator management interfaces to authorized administrative networks only.
🧯 If You Can't Patch
- Implement strict access controls and monitor sponsor user activities for unusual log access patterns.
- Regularly review and audit sponsor-level user accounts, removing unnecessary permissions and accounts.
🔍 How to Verify
Check if Vulnerable:
Check FortiAuthenticator version via web interface (System > Dashboard) or CLI (get system status). If version is between 6.3.0-6.6.6, the system is vulnerable.Check Version:
get system statusVerify Fix Applied:
Verify version is 6.6.7 or later via web interface or CLI command 'get system status'.📡 Detection & Monitoring
Log Indicators:
- Unusual log download activities by sponsor users
- Multiple log access attempts from sponsor accounts
- Access to log endpoints outside normal patterns
Network Indicators:
- HTTP requests to log download endpoints from sponsor users
- Unusual data transfer volumes from FortiAuthenticator
SIEM Query:
source="fortiauthenticator" AND (url="*/log/download*" OR url="*/logs/*") AND user_role="sponsor"