Key takeaways

  • SEGA Fave, SEGA's arcade business, found that third parties had accessed some of its servers behind ALL.Net, the network that connects arcade machines in game centers across Japan, and Aime, the card system that identifies players and keeps their progress.
  • It stopped every service tied to ALL.Net and Aime at 15:00 on November 1. As of November 6, there was no restart date. SEGA Fave said it would update on social media around 09:00 on November 8.
  • The stop reaches beyond SEGA's own games. Bandai Namco's ALL.Net titles, including Taiko no Tatsujin and Mario Kart Arcade GP DX, are affected too, along with SEGA's Initial D, maimai and CHUNITHM.
  • SEGA Fave says its initial investigation found no leak of customer or partner data, and that payment data was not on the affected servers. It has not said how the attackers got in.
  • For arcades, the result is dark cabinets, removed machines and cancelled tournaments, with no date for when the games come back.

What happened#

According to SEGA Fave's notice of November 2, a third party gained unauthorized access to some of its servers related to ALL.Net, its arcade game network service, and Aime, its player card system. Since finding the access, it has been investigating whether data was taken and how far the intrusion reached.

To investigate and confirm the systems are safe, it stopped all ALL.Net and Aime related services from 15:00 on Sunday, November 1. As of 18:00 on November 2, these were unavailable:

  • Online play in ALL.Net titles
  • Play using Aime cards
  • Play using PrizeON, used in some prize machines
  • ALL.Net titles' .NET player services and the store locators on their official sites
  • SEGA Lucky Kuji Online, an online prize lottery
  • New SEGA ID registration

SEGA Fave says its initial investigation found no exfiltration of data about customers or business partners, and that payment information, including card data, is not held on the servers that were accessed. It expects the investigation to take some time and will announce a restart once it has finished checking.

It has not said when the access began, how it was found, or how the attackers got in.

Why one network stopped so many games#

ALL.Net connects arcade machines to SEGA's servers for online play, updates and player data. Aime is the card players tap to log in, so that their scores, ranks and unlocked content follow them from machine to machine. Several titles from Bandai Namco Experience also run on ALL.Net, and SEGA Fave's notice points their players to Bandai Namco for details.

So when SEGA Fave stopped both systems, games built around them stopped or ran with limits, whichever company made them. Titles reported as affected include:

Publisher Titles
SEGA Initial D THE ARCADE, maimai DX, CHUNITHM, Eiketsu Taisen
Bandai Namco Taiko no Tatsujin, Mario Kart Arcade GP DX, Mobile Suit Gundam Extreme Vs. 2 Infinite Boost, Gundam Arsenal Base, Wangan Midnight Maximum Tune 6RR PLUS

What it looks like in the arcades#

ITmedia visited a game center near Tokyo on the afternoon of November 5 and found rows of cabinets that were silent or dark, and few customers. Arcades have posted on social media that games are stopped or limited, that some cabinets have been removed from the floor, and that planned tournaments have been cancelled. Crane games and other machines that do not depend on the network kept running.

The outage also reached the industry's trade show. At AMUSEMENT EXPO 2026, held on November 6 and 7 in Tokyo, SEGA Fave withdrew its Initial D THE ARCADE exhibit, according to ITmedia.

What we don't know yet#

  • How the attackers got in, and when the access began
  • Whether any player data was taken. SEGA Fave's "no exfiltration found" applies to its initial investigation
  • What data the affected servers hold. Aime and SEGA ID link players' cards and accounts to their play records; whether any personal data such as email addresses sits there has not been stated
  • Whether this is ransomware or extortion. As of November 6, we have not seen SEGA on leak sites tracked by ransomware.live
  • When the services return, and whether they will come back in stages

Our view#

Stopping everything was the cautious call. When a company does not yet know how far an intruder reached, taking connected services offline is a reasonable way to stop further damage, even at a high cost. SEGA Fave has also been clear about which services are down and has said when it will next update. That clarity helps the arcades that have to decide what to do with their floors.

A shared network is shared risk. ALL.Net and Aime are infrastructure for a whole industry, not only for SEGA's own games, and Bandai Namco's titles went dark with SEGA's. Any company that builds on a partner's network for logins and online features inherits that partner's incidents. Arcade operators, who pay for the machines and the floor space, have no control over either.

Games that need the network to run at all. The length of this outage shows the cost of designs where a game cannot be played, or can only be played in a reduced form, when its login and data service is offline. For services that venues and customers depend on, it is worth planning in advance what can still work in a degraded mode, so that an emergency stop of the central systems does not stop everything else.

What this means for practitioners#

  • Map your dependencies on partners' platforms. Know which of your products stop if a partner takes its network or login service offline, and agree in advance how you will be told and when.
  • Design a degraded mode. Decide what can keep working, safely, without the central service, such as offline play with later sync, and test it.
  • Prepare the precautionary shutdown. If you may need to stop everything during an incident, plan the order of restoration, who decides, and how you will inform the businesses that depend on you.
  • Give a next-update time. When there is no restart date, saying when the next update will come is the most useful thing for everyone waiting.

Japanese terms at a glance#

Japanese Reading Meaning
ゲームセンター（ゲーセン） gēmu sentā (gēsen) Game center, arcade
筐体 kyōtai Arcade cabinet
緊急メンテナンス kinkyū mentenansu Emergency maintenance
不正アクセス fusei akusesu Unauthorized access
データ流出 dēta ryūshutsu Data exfiltration, leak
稼働停止 kadō teishi Taken out of operation
大会中止 taikai chūshi Tournament cancelled
復旧のめど fukkyū no medo Prospect of restoration