Exploited vulnerabilities / CVE-2026-39808
Confirmed exploited · command injection · Fortinet FortiSandboxCVE-2026-39808
Fortinet FortiSandbox command injection, confirmed exploited in the wild.
Fortinet FortiSandbox contains an OS command injection vulnerability that could allow an unauthenticated attacker to execute unauthorized code or commands via crafted HTTP requests.
| CISA's name for it | Fortinet FortiSandbox OS Command Injection Vulnerability |
|---|---|
| Vendor and product | Fortinet · FortiSandbox |
| Type | command injection · CWE-78 |
| Exploited | Confirmed by CISA listed 16 July 2026 |
| Likelihood | one of the most likely to be exploited of every vulnerability tracked |
| Deadline | 19 July 2026 · already passed |
| Used in ransomware | Not reported |
| Advisories | fortiguard.fortinet.com ↗ · www.cisa.gov ↗ · www.cisa.gov ↗ · nvd.nist.gov ↗ |
Three steps, in this order
Apply the vendor fix; command injection on an exposed device is used within days of disclosure.
Restrict the management interface to a trusted network until the fix is in.
Review the device's logs and configuration for changes you did not make.
| CISA's required action | 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. |
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Know before someone else finds it
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CVE-2026-39808 in short
Is CVE-2026-39808 being exploited?
Yes. CISA added CVE-2026-39808 to its Known Exploited Vulnerabilities catalogue on 16 July 2026, which it does only on evidence of exploitation in the wild.
What is the CISA deadline for CVE-2026-39808?
US federal agencies must remediate it by 19 July 2026. Everyone else should treat that date as the latest safe point to patch an internet-facing system.
How likely is CVE-2026-39808 to be exploited in the next 30 days?
FIRST's Exploit Prediction Scoring System gives it 93%, the 99th percentile of every CVE it scores.
How do I fix CVE-2026-39808?
Apply the vendor fix; command injection on an exposed device is used within days of disclosure. Restrict the management interface to a trusted network until the fix is in. Review the device's logs and configuration for changes you did not make.
Other Fortinet vulnerabilities being exploited
| CVE | Product | Type | Listed |
|---|---|---|---|
| CVE-2025-61624 | Multiple Products | path traversal | 16 October 2026 |
| CVE-2026-104286 | FortiMail | path traversal | 1 October 2026 |
| CVE-2025-25249 | Multiple Products | memory corruption | 9 September 2026 |
| CVE-2025-68686 | FortiOS | exploited vulnerability | 27 July 2026 |
| CVE-2026-25089 | FortiSandbox | command injection | 16 July 2026 |
| CVE-2026-21643 | FortiClient EMS | SQL injection | 13 April 2026 |
Sources: CISA Known Exploited Vulnerabilities catalogue (released 10 November 2026) and FIRST EPSS. Page compiled automatically by SAK T.L.M, the threat-intelligence tool of SAK T.E.C, on 13 November 2026.