FortiOS 4.0
4.0Fortinet · OS release · FortiOS Series
Unsupported since · 5373 days ago
FortiOS 4.0 reached end of support on (5373 days ago).
- Notice published
- 17y 9mo ago
- End of support
- 14y 9mo ago
Lifecycle Milestones
| Lifecycle notice published | 17y 9mo ago | |
|---|---|---|
| Last date of support | 14y 9mo ago |
Known Exploited Vulnerabilities
6 CVEs in CISA's Known Exploited Vulnerabilities catalog are recorded against the Fortinet platform this release belongs to and may apply to this release; verify against the vendor advisory before acting. Fortinet support for this release stopped on . Where one applies, upgrade, isolate, or compensate.
| CVE | KEV added | Vulnerability | Flags |
|---|---|---|---|
CVE-2025-68686
|
Fortinet FortiOS Exposure of Sensitive Information to an Unauthorized Actor Vulnerability
KEV added 2026-07-27
|
||
CVE-2019-6693
|
Fortinet FortiOS Use of Hard-Coded Credentials Vulnerability
KEV added 2025-06-25 · Ransomware
|
Ransomware | |
CVE-2018-13374
|
Fortinet FortiOS and FortiADC Improper Access Control Vulnerability
KEV added 2022-09-08 · Ransomware
|
Ransomware | |
CVE-2021-44168
|
Fortinet FortiOS Arbitrary File Download
KEV added 2021-12-10
|
||
CVE-2019-5591
|
Fortinet FortiOS Default Configuration Vulnerability
KEV added 2021-11-03 · Ransomware
|
Ransomware | |
CVE-2020-12812
|
Fortinet FortiOS SSL VPN Improper Authentication Vulnerability
KEV added 2021-11-03 · Ransomware
|
Ransomware |
Source: CISA Known Exploited Vulnerabilities catalog. The Ransomware flag reflects CISA's own knownRansomwareCampaignUse field, set when the CVE has been observed in ransomware campaigns per their threat intel. It's not a property of the vulnerability description itself.
Correlation is at the platform level, not per-OS-version (entries disclosed well before this release train shipped are left out). Not exhaustive: KEV only lists actively-exploited CVEs and many relevant unexploited vulnerabilities are not here. Verify against vendor security advisories (PSIRT, JSA, PAN-SA) and NVD before acting. See compensating controls if refresh isn't immediate.
Is FortiOS 4.0 still maintained?
No. Fortinet no longer maintains FortiOS 4.0; support ended on 2012-02-24. It receives no fixes of any kind, including security patches. Plan an upgrade to a maintained release. See Fortinet's lifecycle bulletin.
When do security fixes for FortiOS 4.0 stop?
Fortinet has not published an end-of-engineering date for FortiOS 4.0.
What should I upgrade FortiOS 4.0 to?
Upgrade to a currently maintained Fortinet release. Check Fortinet's release notes for the recommended version.
Which known-exploited CVEs may apply to the FortiOS 4.0?
6 CVEs in CISA's Known Exploited Vulnerabilities catalog are recorded against Fortinet FortiOS and may apply to FortiOS 4.0, whose security fixes stopped on 2012-02-24. Verify each against the vendor advisory for the fixed releases before acting. See the Known Exploited Vulnerabilities table for the full list.
FortiOS 4.0 Release Lifecycle
FortiOS 4.0 is a Fortinet FortiOS software release. Releases are maintained on a fixed schedule: Fortinet ships fixes and security patches until the release reaches end of engineering, after which a device must be upgraded to a maintained release to stay patchable. The dates below are milestones for the software train, not for any specific appliance — hardware running this release has its own separate lifecycle. This product has reached end of life as of , meaning Fortinet no longer provides technical support, software updates, or hardware replacement for this product. Organizations still running the FortiOS 4.0 should plan a migration .