How severe is CVE-2026-39808?

CVE-2026-39808 has a CVSS 3.x base score of 9.8, rated critical severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.

Is CVE-2026-39808 being actively exploited?

Yes. CVE-2026-39808 is on CISA's Known Exploited Vulnerabilities (KEV) catalog, added on 2026-07-16, which means active exploitation has been confirmed. It should be prioritised for remediation.

What products are affected by CVE-2026-39808?

CVE-2026-39808 affects Fortinet Fortisandbox. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2026-39808?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Because this CVE is known to be actively exploited, treat remediation as urgent — CISA KEV typically sets a short remediation deadline.

Does CVE-2026-39808 have an EU (EUVD) identifier?

Yes. CVE-2026-39808 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-22338.

When was CVE-2026-39808 published?

CVE-2026-39808 was published on 2026-04-14 and last updated on 2026-07-17.

CVE-2026-39808

CVE-2026-39808 is a critical-severity vulnerability in Fortinet Fortisandbox with a CVSS 3.x base score of 9.8. It is listed in CISA's Known Exploited Vulnerabilities (KEV) catalog, confirming it has been exploited in the wild (added 2026-07-16). The underlying weakness is classified as CWE-78.

Key facts

Severity: Critical (CVSS 3.x base score 9.8)
EPSS exploit prediction: 91% (100th percentile)
Actively exploited: Yes — listed in CISA KEV (added 2026-07-16)
EU (EUVD) id: EUVD-2026-22338
Weakness: CWE-78
Affected product: Fortinet Fortisandbox
Published: 2026-04-14
Last modified: 2026-07-17

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>

Frequently asked questions

What is CVE-2026-39808?: 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>
How severe is CVE-2026-39808?: CVE-2026-39808 has a CVSS 3.x base score of 9.8, rated critical severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2026-39808 being actively exploited?: Yes. CVE-2026-39808 is on CISA's Known Exploited Vulnerabilities (KEV) catalog, added on 2026-07-16, which means active exploitation has been confirmed. It should be prioritised for remediation.
What products are affected by CVE-2026-39808?: CVE-2026-39808 affects Fortinet Fortisandbox. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2026-39808?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Because this CVE is known to be actively exploited, treat remediation as urgent — CISA KEV typically sets a short remediation deadline.
Does CVE-2026-39808 have an EU (EUVD) identifier?: Yes. CVE-2026-39808 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-22338.
When was CVE-2026-39808 published?: CVE-2026-39808 was published on 2026-04-14 and last updated on 2026-07-17.

References

Affected products (1)

cpe:2.3:a:fortinet:fortisandbox:*:*:*:*:*:*:*:*

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