DeviceSunsetCheck
FR

ASUS

ASUS RT-N66U: aging N900 security

The RT-N66U is an older-generation N900 router for which ASUS has slowed and then stopped security firmware updates.

Risk level
High risk
Category
Routers and network
Last reviewed
2026-05-23
Confidence
medium

Support status

Security support stopped or heavily slowed: check the ASUS changelog for this model.

Typical symptoms

  • Firmware on old version
  • Telnet access active by default
  • ASUSWRT exposed without recent update

Fixes to try

  • Install OpenWrt if the model is supported
  • Disable Telnet, WAN SSH and remote admin
  • Segment the network to isolate critical devices

Alternatives

  • ASUS RT-AX58U (Wi-Fi 6)
  • TP-Link Archer AX73
  • ASUS ZenWiFi AX mesh router

Affiliate links appear only when an approved replacement offer is configured.

Sources to verify