The exposure mechanism
Grok Build, SpaceXSI’s coding agent, allegedly exposed confidential information belonging to thousands of users through links intended for sharing apps created with the platform. Ars Technica reports this, citing research by security firm Claroc. The links consist of random words placed to the left of the grok.me domain, a choice that according to the researchers makes it possible to enumerate them via passive DNS services, which publicly log resolutions of previously unseen addresses. In most cases, clicking the link opens the application with all associated data.
Ars Technica notes that the default setting for links is reportedly “anyone with the link,” while users can switch to “invited users” or “only you.” According to Claroc, a passive DNS search returned 43,601 grok.me addresses, of which more than 35,000—almost 95 percent—were publicly accessible. The article draws a comparison with Google, which places the random part of the URL after the domain: in that case, the links would not be visible to passive DNS services.
The data found and the internal case
Among the exposed materials, again according to Claroc, are internal business plans, advertising proposals, medical reports, checklists from a luxury cruise company, and employee names and identification numbers. Twenty-four apps were reportedly built by SpaceXSI itself, formed from the merger of SpaceX and xAI: among the documents cited are an onboarding plan marked confidential for a new member of the enterprise sales team, a map of 594 accounts, internal addresses for sales team tools, and advertising proposals.
The researchers described the incident as surprising, observing that a tool purchased for the same purpose would have been protected by corporate authentication. Ars Technica says it contacted SpaceXSI and that the company began removing the links within hours, until all 24 apps returned an “app not found” error. Claroc CTO Asaf Aprozper said he was notifying the organizations involved, and the cruise company reportedly activated its security team after being informed.
The response and the limits of the incident
A Cursor spokesperson, the coding service acquired by SpaceXSI, claimed that Grok Build apps are private by default and that nothing becomes public without the creator’s choice. According to Ars Technica, Aprozper’s tests contradict this account, because in all cases it would have been necessary to manually change the setting. The spokesperson reportedly did not answer follow-up questions, including whether the exposure was intentional, why the data was removed after the newspaper’s request, and whether customers would be notified.
The research concerns mainly Grok Build, but Aprozper indicates that other app-building tools with their own web addresses, such as Lovable, Bolt and Replit, would be exposed to the same type of enumeration, albeit with less sensitive data found. The overall picture therefore remains open: the figures cited come from the security firm, Cursor’s statements have not been confirmed, and it is not known how many of the removed links concerned third-party data. The operational recommendation in the article is that those using shareable links on Grok Build choose the invited users option.
