Fortinet has released September 2026 security updates addressing multiple vulnerabilities across its products. One high‑severity vulnerability (CVE-2025-25249), confirmed to be activley exploited. The vulnerabilities may result in unauthorized access, system compromise, or disruption of services.

Affected Systems:

The affected systems and versions include, but are not limited to:

• FortiOS: versions 7.6.0 – 7.6.7, 7.4.0 – 7.4.11, 7.2.0 – 7.2.11, 7.0.0 – 7.0.17

• FortiSIEM: versions 7.5.0 – 7.5.1, 7.4.1 – 7.4.2,

• FortiAnalyzer: versions 7.6.3 - 7.6.6.

• FortiSOAR on‑premise: versions 7.6.0 – 7.6.6, 7.5.0 –7.5.3, 7.4.0 – 7.4.5, 7.3.0 – 7.3.3

• FortiSandbox on‑premise: versions 5.2.0, 5.0.0 – 5.0.6, 4.4.0 – 4.4.9

• Fortiweb: versions 8.0.0 –  8.0.2, 7.6.0 – 7.6.5, 7.4.0 – 7.4.12, 7.2.0 – 7.2.13, 7.0.0 – 7.0.12

Security Risks

Successful exploitation of these vulnerabilities may allow unauthorized access, arbitrary command execution, privilege escalation, data exfiltration, or service disruption. For more information on the vulnerabilities addressed in this release, refer to the OpenCVE – Fortinet Vendor Feed.

Recommended Actions

The National Cyber Security Authority (NCSA) strongly recommends that system administrators:

1. Follow Fortinet Security Advisory to lower the risk of potential exploits, protect systems, and ensure their security.

2. Apply the required and latest security updates as soon as possible.
The released software versions for upgrade include, but are not limited to:

• FortiOS: Upgrade to version 7.6.7 or above, 7.4.12 or above, 7.2.12 or above, 7.0.18 or above.

• FortiSIEM: upgrade to version 7.6.0 or above , 7.5.2 or above  

• FortiAnalyzer: Upgrade to version 8.0.0 or above, 7.6.7 or above.

• FortiSOAR on premise: upgrade to version 8.0.0 or above, 7.6.7 or above, 7.5.4 or above.

• FortiSandbox on‑premise: upgrade to version 5.2.1 or above , 5.0.7 or above,  4.4.10 or above

• FortiWeb: Upgrade to version to version 8.0.3 or above, 7.6.6 or above , 7.4.13 or above

3. Before performing any update tasks, ensure that you have a backup of your data.

For further information and support, please contact NCSA by email at rwcsirt@ncsa.gov.rw or call us at 9009.

References

• https://www.fortiguard.com/psirt

• https://app.opencve.io/cve/?vendor=fortinet

• Fortinet Patches Critical Vulnerabilities in FortiMonitorOnSight, Chrome Extension

• Fortinet end-of-life & end-of-support dates — FortinetEOL