They weren’t updating the games, so… down they go.
The main Wii U games affected by the security vulnerability disclosed in December have been taken offline, either for fixes or removal of the attack vector entirely.
Nintendo’s network status page has updated with the below note for the 2014 and 2015 releases:
We have identified vulnerabilities with online play for this network service and have begun temporary emergency maintenance.
We expect an extended maintenance duration while we address these issues and have not determined when online play will resume.
We sincerely apologize for this inconvenience and appreciate your understanding.
An error 106-8011 would appear if trying to play the affected games online.
The ENBufferPwn exploit is a critical vulnerability that affected Nintendo online games dating back to 2011’s Mario Kart 7: it could be used for a full takeover of the console including possibly activating the cameras and audio recording functions of the Wii U GamePad and the 3DS. The affected Switch games and the aforementioned Mario Kart 7 were updated to fix the game at the application level.