CVE-2026-25089 — Fortinet FortiSandbox OS Command Injection Vulnerability
Fortinet FortiSandbox, FortiSandbox Cloud, and FortiSandbox PaaS contain an OS command injection vulnerability that allows an unauthenticated attacker to execute unauthorized commands via specifically crafted HTTP requests.
- CVSS
- 9.8 (Critical)
- KEV status
- CISA KEV — Listed
- First seen (CISA KEV)
- Recommended change window
- Emergency change — patch FortiSandbox management planes within one weekend maintenance window; isolate the management VLAN in the meantime.
- Vendor advisory
- https://fortiguard.fortinet.com/psirt/FG-IR-26-141
- Affected products
- Fortinet FortiSandbox
Why this one matters to a CAB
FortiSandbox is not an edge device in most deployments — it sits adjacent to the FortiGate cluster and receives detonation samples from the mail gateway and the web filter. Because it processes untrusted content by design, an unauthenticated OS command injection in its management HTTP interface is a straight line from “malware sample arrives” to “sandbox is now attacking the perimeter it was meant to defend.”
Defender’s angle
- Exposure check: run
show system interfaceon the paired FortiGate and confirm no management-plane access policy allowssandbox-mgmtfrom anything other than the SOC jump host VLAN. - Fortinet history: FortiSandbox, FortiWeb, and FortiManager have all shipped unauth command-injection CVEs in the last 18 months; this is a management-plane hygiene story more than a one-off. Standardize on out-of-band management for every Fortinet device before the next advisory lands, not after.
- Compensating control: if the maintenance window slips, block egress from the FortiSandbox VRF to anything that is not the FortiCloud update endpoint. Command injection needs a callback path to be useful, and denying that path buys days.
What to bring to CAB
The Fortinet FortiSandbox firmware matrix (baseline → target build), the FortiCloud reachability check, and evidence that the management VLAN ACL is in place. Coordinate this window with the FortiGate team so the FortiSandbox restart does not cascade into a false “malware inspection down” alert.
Sources
This page summarizes publicly available information from CISA KEV, NVD, and the listed vendor advisory. Change Risk Intel does not publish exploit walkthroughs. Verify with your vendor before scheduling any change window.