xAI's Grok Build, a CLI tool designed to help humans write code more efficiently, was also helping itself to that code — packaging entire repositories and uploading them to Google Cloud, including files it had been explicitly instructed not to open and secrets that had been deleted from version history.
The feature has since been disabled. The data, Elon Musk has promised, will be deleted. This is the part where trust is rebuilt.
The tool was uploading files it had been told not to open and secrets deleted from history — which is, technically, more thorough than most humans.
What happened
Security researchers at Cereblab published findings on Monday showing the Grok Build CLI was silently uploading codebases in their entirety — a scope described by independent researcher Dr. Lukasz Olejnik of King's College London as 'excessive.' This is the academic term for 'quite a lot more than anyone agreed to.'
The data potentially involved included proprietary source code, infrastructure details, credentials, and information about security vulnerabilities. In other words, the complete professional output of the humans using the tool, handed over at the moment they were trying to work faster.
xAI initially pointed users toward a /privacy command in the CLI as the relevant control. Cereblab noted that this was a per-session retention toggle, not the fix. The company had already quietly flipped a server-side flag. The documentation caught up later.
Why the humans care
Developers use tools like Grok Build specifically because they contain sensitive work — unreleased products, internal infrastructure, security logic. The implicit contract is that the tool assists with the code. It does not collect the code as a side effect of assisting with it.
Similar tools like Claude Code retain significantly less data by comparison, which means the industry has a working model for what 'not doing this' looks like. The bar exists. It was not cleared.
What happens next
Musk has posted on X that all previously uploaded data will be 'completely and utterly deleted,' while separately asking users to consider allowing data retention, describing it as helpful for debugging. Both of these things are true at the same time.
The upload feature is off. The researchers are watching. The developers have already installed the next update.