Fortinet PSIRT AdvisoriesFG-IR-26-141

Second-Order OS Command Injection via JSON Input on start vnc feature

CVSSv3 Score: 9.1 An improper neutralization of special elements used in an OS command vulnerability [CWE-78] in FortiSandbox, FortiSandbox Cloud and FortiSandbox PaaS WEB UI may allow an unauthenticated attacker to execute unauthorized commands via specifically crafted HTTP requests. Revised on 2026-06-09 00:00:00

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9.1CVSS out of 10Critical severity

Scope

What the vendor says is affected

FortiSandbox
FortiSandbox Cloud

Timeline

When this advisory changed

Jun 9, 2026 at 7:00 AM UTC
Published by Fortinet
The publication date reported by the vendor.
Aug 20, 2026 at 2:50 AM UTC
Added to SecurityAlert
We collected the advisory from the official source.
Sep 6, 2026 at 11:50 PM UTC
Confirmed at the source
Our collector saw this advisory during a later source check.

Source

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Vendor: Fortinet
Advisory ID: FG-IR-26-141
Last source check: Sep 13, 2026 at 5:10 AM UTC

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What the vendor says is affected

When this advisory changed

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