What is CVE-2026-107656?

CVE-2026-107656 is a critical-severity vulnerability in Fortinet Fortisandbox, classified under Authentication Bypass Using an Alternate Path or Channel. CVSS score: 9.8/10. Published 2026-10-26.

How severe is CVE-2026-107656?

Critical severity. CVSS v3 base score is 9.8 out of 10.

Vulnerability in Fortinet Fortisandbox

CVE-2026-107656

An authentication bypass using an alternate path or channel vulnerability in Fortinet FortiSandbox 5.0.0 through 5.0.6, FortiSandbox 4.4.0 through 4.4.9, FortiSandbox 4.2 all versions, FortiSandbox PaaS 5.0.0 through 5.0.6, FortiSandbox PaaS 4.4 all versions, FortiSandbox PaaS 4.2 all versions may allow attacker to execute unauthorized code or commands via crafted HTTP requests

Published 2026-10-26 · last modified 2026-10-26.

CVSS v3 metric

CVSS v3 base score 9.8 (Critical). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H.

EPSS exploit prediction

No EPSS score from FIRST.org yet. New CVEs usually get one within a few days; no score means no signal yet, not low risk. How EPSS works.

Affected products

Weakness classification (CWE)

CWE-288 — Authentication Bypass Using an Alternate Path or Channel

References

fortiguard.fortinet.com/psirt/FG-IR-26-185

Frequently asked questions

What is CVE-2026-107656?: CVE-2026-107656 is a critical-severity vulnerability in Fortinet Fortisandbox, classified under Authentication Bypass Using an Alternate Path or Channel. CVSS score: 9.8/10. Published 2026-10-26.
How severe is CVE-2026-107656?: Critical severity. CVSS v3 base score is 9.8 out of 10.