Svmuu reports that OpenAI has confirmed a supply chain attack targeting a malicious TanStack NPM package in its internal environment, infecting two employees' devices. While user data and core code were not affected, the attackers stole access credentials for some internal code repositories, including code signing certificates used for iOS, macOS, and Windows products.
To prevent hackers from exploiting the stolen certificates to distribute counterfeit applications, OpenAI has initiated defensive certificate rotation and announced that all macOS users of ChatGPT desktop, Codex, and Atlas browsers must upgrade to the latest version by June 12, 2026. After this deadline, old certificates will be revoked, and system-level blocks will prevent the launch of older versions and new installations.
OpenAI stated that the company had previously deployed stricter code package blocking policies, but the infected devices had not yet synchronized the latest configuration, allowing the malicious component to successfully infiltrate. Currently, the iOS and Windows clients are unaffected, and core data such as user account passwords and API keys have been confirmed secure.