External risk intelligence

Fortinet FortiSandbox OS Command Injection Vulnerability

CVE advisorySeverity: CRITICAL (CVSS 9.8)

CVE-2026-25089

An OS command injection vulnerability in Fortinet FortiSandbox may allow an unauthenticated attacker to execute unauthorized commands. This could impact the functionality and security of network security devices if reachable via specially crafted HTTP requests.

5Halo Surface Signal

OS Command Injection

Fortinet Fortisandbox

4.2.0 to 4.2.84.4.0 to before 4.4.95.0.0 to before 5.0.65.0.4 to before 5.0.6

External exposure likelihood

Halo Surface Signal score for CVE-2026-25089

FortiSandbox is an enterprise security appliance typically deployed at the network edge or in close proximity to gateways to inspect incoming traffic. As a network security product designed to handle external inputs, it is frequently exposed to the public internet or sits in a position where it is reachable by untrusted traffic.

PCI scan relevance

PCI Relevance for CVE-2026-25089

Yes

CVE-2026-25089 — Halo PCI Relevance: Yes. Under typical PCI ASV external scan criteria, this issue may be flagged for scan prioritization.

This OS command injection vulnerability in Fortinet FortiSandbox allows unauthenticated attackers to execute unauthorized commands, which can lead to a PCI scan failure.

Scan-prioritization guidance only—not a PCI DSS certification or ASV attestation.

Horizon Alert

Summary of the vulnerability and why it matters

A vulnerability in Fortinet FortiSandbox products could allow an attacker to run unauthorized commands on affected systems through specially crafted web requests.

  • Unauthorized command execution possible.
  • Affects network security devices.
  • Confirm relevance and exposure.

Attack Path

How an attacker could exploit the issue

An unauthenticated attacker can send specially crafted HTTP requests to a vulnerable FortiSandbox appliance. This could allow them to execute arbitrary operating system commands on the affected device.

  • Requires network access.
  • Triggered by crafted HTTP requests.
  • Enables unauthorized command execution.

Live Threat

Current exploitation, exposure, and threat context

A vulnerability in Fortinet FortiSandbox could allow an unauthenticated attacker to execute unauthorized commands by sending specially crafted HTTP requests. This could affect the behavior of the service when supported by the advisory.

  • System commands execution at risk.
  • Via crafted HTTP requests.
  • Unauthorized command execution.

Priority actions

Operational Fix

Recommended remediation, mitigation, and detection steps

The real-world ownership of this vulnerability likely falls to teams managing network security infrastructure, such as dedicated security operations or network engineering teams, in coordination with application owners responsible for the FortiSandbox deployment. The critical first step is to identify all instances of the affected technology, confirm their exposure and business criticality, and then ascertain the specific accountable owner before planning remediation.

  • Network and Security teams own remediation.
  • Verify external reachability and criticality.
  • Plan maintenance for updates and testing.

Frequently asked questions

What is Fortinet FortiSandbox?

FortiSandbox is an enterprise-grade security appliance designed to analyze files and traffic to detect advanced threats. It operates by simulating environments where suspicious activity can be safely observed, making it a critical component for identifying malicious intent within network traffic before it reaches internal systems.

What does OS command injection mean for CVE-2026-25089?

This vulnerability falls under the CWE-78 weakness class, which happens when software fails to properly filter user-supplied input before passing it to a system command. In this case, the flaw allows an attacker to send unauthorized commands directly to the device's operating system, potentially giving them control over the underlying platform.

How is this vulnerability triggered?

An attacker triggers the vulnerability by sending a specifically crafted HTTP request to the target device. Because this flaw involves input handling, requests that do not follow the specific malicious pattern required to bypass input sanitization will not execute unauthorized commands.

Is my device at risk based on Halo Surface Signal?

Halo Surface Signal indicates that FortiSandbox devices are frequently placed at the network edge or near gateways to inspect traffic. Because the appliance is designed to handle external inputs, any instance reachable from untrusted networks or the public internet faces a significantly higher risk of being targeted by this flaw.

Do I need to take action if I run FortiSandbox?

Yes, start by identifying all instances of FortiSandbox within your environment and verifying their network reachability. Coordinate with your network and security teams to assess which systems are exposed and ensure you are prepared to apply necessary updates or configuration changes once they are available.

References