If you use the CASIO WATCHES app, you might have noticed that some of its features are currently unavailable. This is because Casio has temporarily suspended certain app services following the discovery of a critical security issue affecting PHP, a programming language widely used to power web services.
The Japanese watchmaker announced the suspension on 22 October 2026, although its official notice states that it took effect a day earlier, on 21 October. The company says the move is a precautionary measure to protect customer information, as parts of the app’s service rely on PHP.

The company did not confirm any breaches to the services or leakage of customer information at the time of writing. The brand also stressed that the security issue affects technology used by web services worldwide and is not exclusive to its own systems.
It’s worth noting that Casio’s notice did not specify which app functions or services have been affected. The company also did not state that all connected-watch features are unavailable, leaving the full extent of the disruption unclear for individual watch models and app operations.

The brand’s suspension notice does not specify which app functions or services have been affected. As such, it remains unclear how much the disruption impacts different watch models and the app’s day-to-day use. The company has also not stated that all connected-watch features are unavailable, so the extent of the disruption remains uncertain.
Casio did not provide a date when the app’s services will return to full functionality. That said, the company says that it is working as quickly as possible to amend that. The company apologises for the inconvenience caused by the suspension.
(Source: Casio International)

