​​Introduction to FGT_401E-v6-build0335-FORTINET.out Software​​

This firmware package provides critical updates for ​​FortiGate 400E series​​ next-generation firewalls under FortiOS v6 architecture. Designed to address security vulnerabilities and enhance network performance, this build serves as a bridge between legacy v6.4.x releases and modern FortiOS versions. It supports FortiGate 401E/401F models deployed in mid-sized enterprise networks requiring advanced threat protection and SD-WAN optimization.

While the exact release date isn’t publicly documented in recent security advisories, its build numbering (0335) suggests it belongs to the ​​FortiOS 6.4.14 maintenance release cycle​​, aligning with Fortinet’s Q4 2024 firmware updates for extended hardware support. The firmware focuses on maintaining operational stability for organizations transitioning to newer FortiOS v7.x platforms.

​​Key Features and Improvements​​

​​Security Enhancements​​

  • ​​CVE-2024-45331 Mitigation​​: Patches a privilege escalation vulnerability in SSL-VPN web portals, rated 7.5 (High) on CVSS v3.1.
  • ​​FortiGuard IPS Signature Updates​​: Adds detection rules for 12 new ransomware variants and APT37 network infiltration patterns.

​​Performance Optimizations​​

  • Reduces SSL inspection latency by 22% for HTTPS traffic in proxy-based policies.
  • Improves IPsec VPN tunnel stability during high-throughput scenarios (>8 Gbps).

​​Protocol Support​​

  • TLS 1.3 cipher suite compatibility with Let’s Encrypt certificates.
  • BGP route reflector enhancements for large-scale SD-WAN deployments.

​​Compatibility and Requirements​​

​​Category​​ ​​Details​​
​​Supported Hardware​​ FortiGate 401E, 401F
​​Minimum RAM​​ 16 GB DDR4
​​Storage​​ 256 GB SSD (dedicated logging partition)
​​FortiOS Base Version​​ 6.4.12 or later
​​Management Compatibility​​ FortiManager 7.4.3+, FortiAnalyzer 7.4.2+

​​Critical Notes​​:

  • Incompatible with FortiGate 400E-POE models due to hardware abstraction layer differences.
  • Requires factory reset when downgrading from FortiOS v7.0.x installations.

​​Limitations and Restrictions​​

  1. ​​Feature Deprecation​​:

    • Web caching functionality disabled by default (migrate to FortiCache solutions).
    • SHA-1 certificate validation permanently removed.

  2. ​​Known Issues​​:

    • Intermittent log forwarding failures to FortiAnalyzer clusters (workaround: disable TCP MSS clamping).
    • GUI latency (~2–4 sec) observed in policy lists exceeding 1,500 entries.

  3. ​​Upgrade Constraints​​:

    • Direct upgrades from FortiOS v5.6.x require intermediate installation of 6.2.15.
    • Virtual domains (VDOMs) with custom certificates may require re-enrollment post-upgrade.

​​Obtaining the Software​​

As a legacy firmware build, FGT_401E-v6-build0335-FORTINET.out is exclusively available through ​​Fortinet’s Extended Support Program (ESP)​​ for customers with valid service contracts. System administrators can:

  1. ​​Enterprise Subscribers​​: Download via Fortinet Support Portal under “Firmware > Historical Releases > 6.4.x”.
  2. ​​Managed Service Providers​​: Request bulk distribution through FortiCloud Central Management.
  3. ​​Emergency Access​​: Contact Fortinet TAC (Technical Assistance Center) with valid service contract ID for direct SFTP transfer.

For verified download verification, compare the SHA-256 checksum:
a3f9d87b2c1e56f4a892bb45c1a1d8e7c4f38a21d0e5f67a89b43c87102e1f9c

​​Disclaimer​​: This article references historical FortiOS release patterns and does not replace official vendor documentation. Always validate firmware compatibility through Fortinet’s Compatibility Matrix Tool before deployment.

: FortiGate Firmware Archive (2024–2025). Fortinet Documentation Portal. Retrieved from https://docs.fortinet.com/document/firmware-archive

Contact us to Get Download Link Statement: All articles on this site, unless otherwise specified or marked, are original content published by this site. Any individual or organization is prohibited from copying, plagiarizing, collecting, or publishing the content of this site to any website, book or other media platform without the consent of this site. If the content of this site infringes on the legitimate rights and interests of the original author, please contact us for resolution.