[BUG] Cowork VM: rootfs.img CDN download hangs indefinitely on launch, burns 100% CPU — macOS 26.3.1, v1.1.5368

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?

Preflight Checklist

• [x] I have searched existing issues and this hasn't been reported in this exact form
• [x] This is a single bug report
• [x] I am using the latest version of Claude Desktop

What's Wrong?

Claude Desktop burns 100% CPU on every launch because the Cowork VM attempts to
download rootfs.img from Anthropic's CDN on startup, and that download never completes.
The app hangs indefinitely waiting for the download. There is no way to disable VM
startup or skip Cowork initialization.

Environment

• OS: macOS 26.3.1
• Claude Desktop version: 1.1.5368
• Hardware: Apple Silicon (Mac)

Steps to Reproduce

1. Launch Claude Desktop
2. Observe 100% CPU in Activity Monitor immediately
3. App never becomes usable — hangs indefinitely

What Happens

• Claude Desktop attempts to download rootfs.img from Anthropic's CDN on every launch
• Download never completes (CDN-side hang, not a local network issue)
• App burns 100% CPU the entire time it waits
• Only resolution is force-quitting the app

Confirmed Isolated

• Reproduced with completely empty MCP config (all connectors removed)
• Full MCP config restored — identical behavior either way
• Config and connectors are definitively NOT the cause
• Nuking vm_bundles directory does not help — re-download attempt hangs identically

Expected Behavior

• Either the download completes successfully, OR
• The app should timeout gracefully and allow use without Cowork, OR
• There should be a user-facing option to disable Cowork VM startup

Logs to Check

~/Library/Logs/Claude/cowork_vm_node.log

Related Issues

• #22543 — 10GB VM bundle performance degradation (macOS)
• #24070 — Cowork VM fails to boot after auto-update (macOS)
• #16646 — Freezing + 12GB VM bundle on macOS

Labels: bug area:cowork platform:macos

What Should Happen?

Claude cowork should launch and work!!!

Error Messages/Logs

Steps to Reproduce

Launch cowork and it just spins with the rainbow ball

Claude Model

Not sure / Multiple models

Is this a regression?

Yes, this worked in a previous version

Last Working Version

_No response_

Claude Code Version

2.1.71 (Claude Code)

Platform

Other

Operating System

macOS

Terminal/Shell

Other

Additional Information

_No response_