CVE-2026-39808 — kevrichment

▼Details

VendorFortinet

ProductFortiSandbox

Vulnerability NameFortinet FortiSandbox OS Command Injection Vulnerability

Date AddedJul 16, 2026

Due DateJul 19, 2026

Required ActionApply 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.

CWECWE-78

PublishedApr 14, 2026

CVSS VectorCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

▼Descriptions

KEV DescriptionFortinet FortiSandbox contains an OS command injection vulnerability that could allow an unauthenticated attacker to execute unauthorized code or commands via crafted HTTP requests.

NVD DescriptionA 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>

▼Compliance (SSVC + BOD 26-04)

Automatableyes

Technical Impacttotal

Exploitation Statusactive

3-Day QualifyingYes

Public Timeline3 days forensic triage

Non-Public Timeline3 days forensic triage

Forensic (Public)Required

Forensic (Non-Public)Required

▼Research Metadata

Last Researched2026-07-17 07:34 UTC

Wall Time0.6s

Searches5

Component Defaultyes

Sourceshttps://www.fortiguard.com/psirt?cve=CVE-2026-39808
https://fortiguard.fortinet.com/psirt/FG-IR-26-100
https://nvd.nist.gov/vuln/detail/CVE-2026-39808
https://github.com/ynsmroztas/FortiSandbox-RCE-Exploit-CVE-2026-39808
https://github.com/samu-delucas/CVE-2026-39808
https://github.com/0xBlackash/CVE-2026-39808
https://cyberpress.org/poc-exploit-released-for-fortisandbox-vulnerability-that-allows-attacker-to-execute-commands/
https://www.sentinelone.com/vulnerability-database/cve-2026-39808/
https://threatprotect.qualys.com/2026/06/17/fortinet-fortisandbox-vulnerability-exploited-by-attackers-cve-2026-39808-cve-2026-25089-cve-2026-39813/

QC Notes

info precondition_contradiction: Preconditions don't mention deployment applicability (component/product version)

warn component_extraction: Component 'FortiSandbox API endpoint' matches or contains product name 'FortiSandbox' — no specific component identified

🎯 Hunting Hypothesishermes

Monitor for unauthenticated HTTP requests to FortiSandbox API (/fortisandbox) with command injection payload patterns in request bodies or parameters.

▼Research Details

ComponentFortiSandbox API endpointhermes

PreconditionsNetwork reachability to FortiSandbox API endpoint (port 443/HTTP management interface) — no authentication required. The OS command injection (CWE-78) exists in FortiSandbox API en… show morehermes

DeliveryHTTP requests to FortiSandbox API endpoint; specially crafted request triggers OS command injection in the API handler. No authentication required.

Public PoCyes

PoC URLshttps://github.com/ynsmroztas/FortiSandbox-RCE-Exploit-CVE-2026-39808
https://github.com/samu-delucas/CVE-2026-39808
https://github.com/0xBlackash/CVE-2026-39808

Advisoryhttps://www.fortiguard.com/psirt?cve=CVE-2026-39808

Exploit NotesCVSS attack complexity: LOW | CRITICAL severity (CVSS 9.8) | Multiple public PoCs available (3 repos) | Unauthenticated remote command injection via API endpoint | Low complexity — requires only network access. FortiGuard advisory FG-IR-26-100. PoC exploit articles published by Cyberpress and SentinelOne. Qualys ThreatPROTECT notes active exploitation alongside CVE-2026-25089 and CVE-2026-39813.

▼Summary

Critical (CVSS 9.8) unauthenticated OS command injection in Fortinet FortiSandbox API endpoint (4.4.0-4.4.8). Three public PoC repos available (ynsmroztas, samu-delucas, 0xBlackash). Root-level RCE and sandbox escape. Actively exploited in the wild. Patch: FortiSandbox 4.4.9.