CVE-2025-47761 is a vulnerability identified in Fortinet's FortiClientWindows VPN client software versions 7.2.0 through 7.2.9 and 7.4.0 through 7.4.3. The root cause is an exposed IOCTL (Input Output Control) interface within the fortips driver component that lacks sufficient access control, categorized under CWE-782. This flaw allows an authenticated local user—meaning someone with valid credentials and local access—to execute unauthorized code or commands on the affected system. Successful exploitation requires the attacker to have an active VPN IPSec connection, which is a prerequisite to interact with the vulnerable driver. Additionally, the attacker must bypass Windows memory protection mechanisms such as Heap integrity and Hypervisor-protected Code Integrity (HSP), which adds complexity to the attack. The vulnerability affects confidentiality, integrity, and availability by potentially allowing privilege escalation and arbitrary code execution, which could lead to full system compromise. The CVSS v3.1 base score is 7.1, reflecting high severity with attack vector local, high attack complexity, low privileges required, no user interaction, and scope changed. No public exploits or active exploitation in the wild have been reported to date. The vulnerability was reserved in May 2025 and published in November 2025. Fortinet has not yet provided patch links, indicating that remediation may be pending or in progress.

For European organizations, this vulnerability poses a significant risk especially to enterprises and government agencies relying on FortiClientWindows for secure VPN access. Exploitation could allow malicious insiders or compromised local users to escalate privileges and execute arbitrary code, potentially leading to data breaches, disruption of services, or lateral movement within networks. Confidentiality of sensitive data transmitted over VPNs could be compromised, and integrity of endpoint systems undermined. Availability could also be impacted if attackers deploy destructive payloads or disrupt VPN functionality. Organizations in sectors such as finance, healthcare, critical infrastructure, and public administration, which commonly use Fortinet VPN solutions, face heightened risk. The requirement for an active VPN IPSec connection means remote attackers cannot exploit this vulnerability without first establishing a VPN session, somewhat limiting the attack surface but still posing a threat in environments with multiple users sharing endpoints or where endpoints are accessible to untrusted users.

1. Apply official patches from Fortinet immediately once they become available to address the exposed IOCTL access control issue. 2. Until patches are released, restrict local user permissions on systems running FortiClientWindows to minimize the number of users who can exploit the vulnerability. 3. Enforce strict endpoint security policies, including application whitelisting and privilege management, to prevent unauthorized code execution. 4. Monitor VPN IPSec connections for unusual activity or unauthorized sessions, as an active VPN connection is required for exploitation. 5. Employ advanced endpoint detection and response (EDR) tools to detect attempts to bypass Windows memory protections such as Heap integrity and HSP. 6. Conduct regular security awareness training to reduce risks from insider threats. 7. Segment networks to limit lateral movement in case of compromise. 8. Review and harden fortips driver access controls if possible through configuration or vendor guidance. 9. Maintain up-to-date backups and incident response plans to quickly recover from potential exploitation.