Japanese car manufacturer Toyota has disclosed a security incident that involved source code hosted on GitHub and which may have resulted in unauthorized access to roughly 300,000 customer email addresses.
The incident, the company says, impacts customers who have subscribed to the T-Connect website, a service and mobile application that provides users with car management features such as find my car, maintenance reminders, concierge services, and vehicle information.
In a data breach notice, the carmaker explains that the root cause of the data breach was a subcontractor uploading Toyota source code to a GitHub repository that was inadvertently set to public access.
Because of this misconfiguration, the source code remained exposed to the internet between December 2017 and September 2022, when public access to the repository was revoked.
The source code, the company says, contained an access key to a server where customer information such as email addresses and management numbers (assigned automatically to each user) were stored.
Toyota says that, immediately after identifying the data breach, it made the GitHub repository private and changed the access key to the impacted server.
However, the company has not been able to determine whether any third party has used the access key to connect to the server, but says it has started sending out apology letters to over 296,000 customers, to warn them of the potential exposure of their email address.
No other customer information – such as names, addresses, phone numbers, or credit card details – was impacted in the incident, as no such data is stored on the potentially exposed server. Email addresses for Lexus vehicles or MyToyota apps were not impacted either.
The carmaker also notes that, while it has no evidence of misuse of the exposed email addresses, impacted customers should be wary of phishing emails and other types of scams.
Toyota has set up a special page on its website that allows users to check whether their email address was exposed in the incident.
In February 2022, the carmaker was forced to suspend production at all its 14 plants in Japan over a suspected cyberattack.