uOS1.39 Update: What's New for USG FLEX H Series

Zyxel_Avani

The latest USG FLEX H firewall series is powered by the new uOS, which is designed to minimize system response time and improve overall system efficiency, including the following features:

• Nebula Identity Federation Service

Centralize identity. Simplify access. Strengthen security. Nebula Identity Federation Service reduces IT overhead and closes identity gaps - your existing SSO investment now covers Captive Portal and SSL VPN* access automatically. Extends federated identity support to Captive Portal and SSL VPN, enabling seamless and secure single sign-on experiences across access methods.

*SecuExtender does not support NID FS

• Passwordless Network Access with NCAS Passkey

Nebula Cloud Authentication Server (NCAS) now supports passkey login for Captive Portal. Deliver fast, phishing-resistant, passwordless network access — managed centrally through Nebula.

• Unusual Device Admin Login Notification

Nebula and SecuReporter now alert you the moment an unusual device admin login is detected—including logins from unexpected countries & devices, or repeated failures. No log-diving required. Know the moment something is wrong.

• Automated Certificate Management with Let's Encrypt*Local GUI only

Zyxel now integrate with Let's Encrypt via the ACME protocol to automatically provision and renew trusted SSL certificates - eliminating manual certificate management and preventing expiry-related outages.

• Additional Enhancements
  • VPN PSK support special characters - support “?” special characters
  • Nebula Application Usage Policy - Define and enforce granular application usage policies directly within Nebula
  • API-driven DDNS integration with Cloudflare DNS -Dynamic DNS integration with Cloudflare is now available.
  • CLI Script*Local GUI only - just upload your scripts and apply configurations to your devices instantly
  • Wireless AP Controller SSID Schedule*Local GUI only - Administrators can now configure time-based SSID schedules through AP Controller.
  • Device Firmware Upgrade Log to Nebula - Firmware upgrade history is now logged and accessible in Nebula.

Release Date: July 27, 2026

Supported Models: USG FLEX 50H/50HP/100H/100HP/200H/200HP/500H/700H