CVE-2026-39808

Fortinet FortiSandbox OS Command Injection Vulnerability

  • Critical 9.1
  • Exploited: added to CISA KEV 16 Jul 2026

Description

A improper neutralization of special elements used in an os command ('os command injection') vulnerability in Fortinet FortiSandbox 4.4.0 through 4.4.8 may allow attacker to execute unauthorized code or commands via <insert attack vector here>

Key facts

Published
14 Apr 2026
Last changed
17 Jul 2026
Assigned by
fortinet
KEV added
16 Jul 2026
KEV fix due
19 Jul 2026
EPSS
93.189% likely to be exploited in the next 30 days, higher than 99.838% of CVEs (scores for 15 Nov 2026)
SSVC (CISA)
Exploitation: active; Automatable: yes; Technical impact: total

Severity scores

Each score is shown as its source gave it. They are not averaged or merged.

  • 9.1CVSS 3.1, Criticalfrom the CNA (fortinet)CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H/E:F/RL:O/RC:C

What to do

  • Upgrade to FortiSandbox version 4.4.9 or above Upgrade to FortiSandbox PaaS version 5.0.2 or aboveCNA solution statement
  • Apply mitigations in accordance with vendor instructions, ensuring compliance with CISA’s BOD 26-04 Prioritizing Security Updates Based on Risk (see URL in Notes) guidance and CISA’s “Forensics Triage Requirements” (see URL in Notes). Follow applicable BOD 26-04 guidance for cloud services or discontinue use of the product if mitigations are unavailable. Stakeholders are responsible for evaluating each asset's internet exposure and ensuring adherence to BOD 26-04 patching guidelines.CISA KEV required action

Historical context and remediation

This reference retains the original CVE publication date. A recent record update does not mean a new attack occurred.

No separately sourced impact summary is available on this page yet. Consult the description, version data and dated exploitation evidence.

Version statuses below come from the CNA. An “unaffected” version is not necessarily a currently supported release or proof of a patch date. EPSS is a dated risk estimate, not a count of historical attacks.

Read the original CVE record.

Affected products

VendorProductVersions
FortinetFortiSandbox
  • Default status: unaffected
  • 4.4.0 up to and including 4.4.8 (affected)
FortinetFortiSandbox PaaS
  • Default status: unaffected
  • 23.4.4374 (affected)
  • 23.4.4350 (affected)
  • 23.3.4329 (affected)
  • 23.1.4245 (affected)
  • 22.2.4151 (affected)
  • 22.2.4134 (affected)
  • 22.1.4113 (affected)
  • 21.4.4072 (affected)
  • 21.3.4055 (affected)

Timeline

  1. 14 Apr 2026 Published
  2. 16 Jul 2026 CVE-2026-39808 added to CISA KEV
  3. 16 Jul 2026 Added to the CISA KEV catalogue

Weakness

Practice this bug class

HackZoneLabs has a hands-on lab on OS command injection (CWE-78).

References