Fortinet FortiClient EMS – Unauthenticated Remote Code Execution (CVE-2026-35616)
Critical Security Bulletin Fortinet FortiClient EMS - Unauthenticated Remote Code Execution (CVE-2026-35616)Advisory: Fortinet PSIRT FG-IR-26-099Published: April 4, 2026Severity: Critical (CVSS 9.1-9.8)Status: Active exploitation observed Executive Summary A critical vulnerability in Fortinet FortiClient EMS (Endpoint Management Server) allows unauthenticated remote attackers to execute arbitrary code via crafted API requests. This issue, tracked as CVE-2026-35616, stems from improper access control in exposed API functionality and requires no authentication or user interaction. Active exploitation has already been observed in the wild, elevating this from a patching priority to an immediate incident response concern. Technical Overview Vulnerability Type: Improper Access Control (CWE-284) Attack Vector: Network (remote, unauthenticated) Component: FortiClient EMS API Attack Complexity: Low Privileges Required: None User Interaction: None The flaw allows attackers to bypass API authentication controls and submit crafted requests that execute arbitrary code on the EMS server. Root Cause Failure to properly enforce authentication and authorization checks within API endpoints…
