Grok's coding agent left 35,000 apps wide open

Researchers say 35,000+ Grok Build links were public, including 24 built by SpaceXSI.

According to Ars Technica and Engadget, citing research from security firm Claroc: Grok Build share links put the random words to the left of the domain, so passive DNS services can capture them in publicly searchable databases. Researcher Aprozper said a passive DNS search returned 43,601 links ending in grok.me, of which more than 35,000, nearly 95 percent, were public.

Claroc found 24 SpaceXSI-built apps exposing data, including a sales territory map of 594 accounts and advertising proposals. Other users' exposed data included 3,784 worker medical exams at a Peruvian construction company and a hospital roster of about 3,565 employees. Claroc notified SpaceXSI on Sunday and got no response. Ars reports SpaceXSI began removing the 24 links within hours of Ars emailing questions, while almost all other data remained available at publication.

What to check: Ars advises Grok Build users to avoid "Anyone with the link" and choose an invite-only option unless an app is meant to be widely available. A Cursor representative said Grok Build apps are private by default; Ars reports Aprozper's tests contradict that.

The facts we checked

According to Ars Technica and Engadget, citing research from security firm Claroc

1. Claroc says Grok Build share links put the random words to the left of the domain (e.g. cinder-crane-sand-frost.grok.me), so passive DNS services can capture them in publicly searchable databases.Reported · Ars Technica
2. Aprozper said a passive DNS search returned 43,601 links ending in grok.me, of which more than 35,000, or nearly 95 percent, were public.Figure · Ars Technica
3. Claroc found 24 SpaceXSI-built apps exposing data, including a confidential onboarding plan for a new enterprise sales team member, a sales territory map of 594 accounts, internal system addresses for sales tools, and advertising proposals.Reported · Ars Technica
4. Exposed data from other users included an occupational-health dashboard with 3,784 worker medical exams at a Peruvian construction company, a hospital staff roster of about 3,565 employees by name and ID, and a Tesla service-center scorecard naming 22 technicians.Reported · Ars Technica
5. Aprozper said his tests showed Grok sets links to "Anyone with the link" by default, with "invited users" and "only you" as alternatives. A Cursor representative said Grok Build apps are private by default. Ars reports Aprozper's tests contradict that.Reported · Ars Technica
6. Claroc notified SpaceXSI on Sunday, got no response, and then tagged Musk and Grok Manager Matt Palmer on X. Ars reports SpaceXSI began removing the 24 app links within hours of Ars emailing questions, and all 24 later returned "app not found".Reported · Ars Technica
7. "We were shocked. The company that makes Grok had its own internal material open to anyone holding the link," Claroc wrote.Quote · Engadget
8. "By our estimate roughly two percent held material serious enough to rate high or critical," Claroc wrote.Quote · Engadget
9. Claroc wrote that SpaceXSI "has not done the same for the apps other Grok users and organizations left open." Ars reported almost all other data remained available when its story was published.Quote · Engadget
10. Aprozper said Lovable, Bolt and Replit also give each app its own web address, so the same DNS records expose them, though he said Grok is where Claroc found by far the most sensitive company data.Reported · Ars Technica
11. Ars reports Claude published artifacts, ChatGPT shared conversations and Gemini share links keep the secret randomness in the URL path, so DNS never sees it.Reported · Ars Technica
12. Ars advises Grok Build users to avoid "Anyone with the link" and choose an invite-only option unless they intend to make an app widely available.Reported · Ars Technica

Sources

• EngadgetA Grok vibe-coding agent leaked sensitive SpaceXSI data
• Ars TechnicaGrok Build coding agent leaks oodles of confidential info, some belonging to SpaceXSI