xAI's Grok Build was uploading your entire codebase to Google Cloud. The privacy toggle was theater.

xAI's Grok Build CLI was silently shipping entire Git repositories to a Google Cloud Storage bucket called grok-code-session-traces.

Not just the files you asked it to read.

Everything.

Unread files, deleted commits, .env credentials, API keys. All of it.

A researcher named Cereblab proved it. He planted a canary file and told Grok to do nothing. The canary showed up in the upload bundle anyway.

The numbers are staggering.

The model's actual work generated 192 KB of traffic.

The background upload channel shipped 5.1 GiB in 73 chunks.

That is 27,800 times more data than the task required.

Here is the part that should make every CISO freeze.

The "Improve the model" privacy toggle did nothing. The server kept returning trace_upload_enabled: true regardless of the setting.

xAI disabled the uploads server-side on July 13. No software update. No security advisory. Just a silent flag flip.

The upload code is still sitting in the current binary. Dormant. Not removed.

xAI could re-enable it tomorrow without pushing a single update.

Elon Musk promised all uploaded data would be "completely and utterly deleted." No timeline. No count of affected users. No verification method.

Audit every developer machine running Grok Build.

Rotate every credential the tool could have touched. Not just files it read. Every tracked file. Every secret in Git history.

If your organization deployed Grok Build to production repos, assume compromise until you can prove otherwise.