Security firm Claroc discovered that Grok Build, the coding agent from SpaceXSI, exposed sensitive data from approximately 35,000 live projects to anyone with access to the correct URL. The vulnerability stems from how SpaceXSI implemented link sharing. Unlike Google's approach, which places randomness to the right of the domain, Grok Build places it to the left, making URLs enumerable through passive DNS services that monitor public DNS lookups.
Claroc found 43,601 total links ending in grok.me, with more than 35,000 or nearly 95 percent being publicly accessible. The exposed data included internal business plans, medical exam results, employee names and ID numbers, and other confidential information. SpaceXSI's own internal data appeared in 24 Grok Build apps built by the company itself, containing onboarding plans marked confidential, sales territory maps with 594 accounts, internal system addresses, and advertising proposals.
Claroc notified SpaceXSI on Sunday. After no response, a Claroc official posted about the issue on X, tagging Elon Musk and Grok Manager Matt Palmer. SpaceXSI removed the links from its 24 apps within hours of receiving an inquiry from Ars Technica. Asaf Aprozper, co-founder and CTO of Claroc, said he is notifying affected companies. After speaking with the luxury cruise company's CISO, that organization "pulled in their whole security team as soon as we shared the findings and are already working to contain the Grok exposure."
A Cursor representative stated that Grok Build "apps are private by default and nothing goes public unless the creator chooses to share it." Aprozper's testing contradicted this, finding that Grok Build required users to manually change sharing settings from "Anyone with the link" to other options. The representative noted that ChatGPT, Lovable, and Bolt also offer shareable links. Aprozper confirmed that Lovable, Bolt, and Replit expose similar risks through DNS records but found "by far the most sensitive company data" on Grok. Platforms including Claude's published artifacts, ChatGPT's shared conversations, and Gemini implement correct practices by placing randomness in the URL path rather than the domain.