FortiLogger Unauthenticated Arbitrary File Upload

Fortilogger is a web-based logging and reporting application for Fortigate Firewalls that runs on Windows. FortiLogger is vulnerable to Arbitrary File Upload. This occurs when a “Content-Type: image/png’’ header is sent to Config/SaveUploadedHotspotLogoFile and then visiting Assets/temp/hotspot/img/logohotspot.asp. As validation of file extensions are not properly managed, an attacker can easily upload a malicious file under ‘Hotspot Settings’. The specially tailored request can be sent by the attacker for remote code execution.

Mitigation / Precaution

• In order to patch this vulnerability, please install the official patch made by the vendor available for supported, vulnerable instances.
• Provide proper validation for file extensions.

Written by

Febna V M

Cyber Security Engineer

Febna once spent an entire evening arguing with an AI chatbot just to prove that machines can be confidently wrong. The debate ended with no clear winner, but it did spark her curiosity for the fascinating world of artificial intelligence. Today, she works at the intersection of AI and cybersecurity, helping build smarter systems while making sure they don’t become too smart for their own good. When she’s not exploring the future of technology, she’s probably asking “but what if?” one more time.