claude-code - 💡(How to fix) Fix [BUG] Write tool bypasses sandbox filesystem write restrictions that Bash tool correctly enforces [2 comments, 3 participants]

The built-in Write tool ignores sandbox filesystem write restrictions configured in settings.json. When sandbox is configured with denyWrite: ["/"] and a limited allowWrite list, the Write tool successfully creates files outside the allowed paths without any error or permission prompt. The Write tool should be blocked from writing files outside the allowWrite list, the same way the Bash tool correctly enforces these restrictions. Writing to a restricted path should fail with a permission error.

Error Messages/Logs

TL;DR

The Write tool in Claude Code may need an update to properly enforce sandbox filesystem write restrictions configured in settings.json.

Guidance

• Review the Write tool's implementation to ensure it checks the denyWrite and allowWrite settings in settings.json before creating files.
• Compare the Write tool's behavior with the Bash tool, which correctly enforces these restrictions, to identify potential differences.
• Test the Write tool with different sandbox configurations to verify its behavior and identify any edge cases.
• Consider adding error handling to the Write tool to return a permission error when attempting to write to a restricted path.

Example

No code snippet is provided as the issue does not include specific implementation details.

Notes

The issue may be specific to the Write tool's implementation or the sandbox configuration in settings.json. Further investigation is needed to determine the root cause.

Recommendation

Apply a workaround by modifying the Write tool to check the denyWrite and allowWrite settings in settings.json before creating files, until a fixed version is available.