AVM rolls out FritzOS 8.25 firmware for Fritz!Box 6690 and 6670 Cable routers

AVM announced the official release of FritzOS 8.25, a new firmware version for its cable‑router line. The update is now available for the Fritz!Box 6690 Cable and Fritz!Box 6670 Cable models, with additional devices slated to receive the upgrade in the coming weeks.

The firmware focuses on improved IPv6 address handling, enhanced stability of the internet connection, and tighter security for VoIP calls through a refreshed digital root certificate. Installation can be performed via the router’s web interface or automatically via the built‑in update function, with the rollout occurring in waves. Users with provider‑branded units (e.g., from Vodafone or PYUR) may need to wait for carrier approval before the update is applied.