[BUG] Sandbox allowLocalBinding: true not applied to child/grandchild processes (breaks Gradle)

Preflight Checklist

• [x] I have searched existing issues and this hasn't been reported yet
• [x] This is a single bug report (please file separate reports for different bugs)
• [x] I am using the latest version of Claude Code

What's Wrong?

  Gradle builds fail in sandbox mode because the Gradle daemon (a forked JVM process) cannot bind to TCP localhost, even when allowLocalBinding: true is configured.

What Should Happen?

Gradle daemon should be able to bind to localhost TCP port for IPC.

Error Messages/Logs

Actual Behavior:
  java.net.SocketException: Operation not permitted
    at sun.nio.ch.Net.bind0(Native Method)
    at TcpIncomingConnector.accept()

Steps to Reproduce

  Steps to Reproduce:

1. Configure sandbox with:

  {
    "sandbox": {
      "network": {
        "allowLocalBinding": true
      }
    }
  }

1. Run any Gradle build:

  ./gradlew build

Claude Model

Opus

Is this a regression?

I don't know

Last Working Version

_No response_

Claude Code Version

2.1.7 (Claude Code)

Platform

AWS Bedrock

Operating System

macOS

Terminal/Shell

Terminal.app (macOS)

Additional Information

Root Cause Hypothesis:

The allowLocalBinding permission applies to the direct child process (./gradlew), but Gradle forks a separate JVM daemon process. This grandchild process doesn't appear to inherit sandbox permissions.