# CVE-2026-39808: Fortinet FortiSandbox OS Command Injection Vulnerability

- Exploited (CISA KEV): yes, added 2026-07-16
- Published: 2026-04-14
- CVSS: 9.1 CRITICAL (v3.1)
- EPSS: 93.2% (100th percentile)
- CWE: CWE-78

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>

## Edge WAF coverage (claimed by vendors, not measured)

| Vendor | Status | First rule | Days after publication |
|---|---|---|---|
| Cloudflare | Blocks by default | 2026-05-04 | 20 |
| AWS | No public claim | — | — |
| Microsoft Azure | No public claim | — | — |
| Google Cloud | No public claim | — | — |
| Fastly | Before feed history | — | — |
| F5 | Rule published | 2026-07-07 | 84 |
| Akamai | No public source | — | — |
| OWASP CRS | No public claim | — | — |

### Cloudflare

- 2026-05-04 · new · rule 9dc1a0b8dbb7425db619309be6e43c37 · default Block
  > Fortinet FortiSandbox - Command Injection - CVE:CVE-2026-39808. Previous action: Log. New action: Block. This is a new detection.
  Source: https://developers.cloudflare.com/changelog/post/2026-05-04-waf-release/

### F5

- 2026-07-07 · new · rule 200103684
  > Added: signature 200103684 "Fortinet FortiSandbox Command Injection" (Command Execution, risk High), systems: Other Web Server. References: CVE-2026-39808.
  Source: https://docs.cloud.f5.com/docs-v2/platform/changelogs/security-details-changelog

## Our test (measured)

- OWASP Core Rule Set 4.25.0, paranoia level 1, anomaly threshold 5, default CRS settings: partial (1 of 2 requests blocked), template CVE-2026-39808, 2026-11-02
- OWASP Core Rule Set 4.25.0, paranoia level 2, anomaly threshold 5, default CRS settings: partial (1 of 2 requests blocked), template CVE-2026-39808, 2026-11-02

"No public claim" means no vendor statement names this CVE; "Before feed history" means the CVE is older than the vendor feed. In both cases generic rules may still block it.

HTML: https://cve.vigilbase.com/cve/CVE-2026-39808 · JSON: https://cve.vigilbase.com/api/v1/cves/CVE-2026-39808