Cowork session fails with 'Failed to create bridge sockets after 5 attempts' after April 16 app update

Description

Every attempt to start a cowork session fails immediately with exit code 1. The Claude Code process inside the VM exits ~800ms after spawning.

Error

From ~/Library/Logs/Claude/cowork_vm_node.log:

[warn] [vm-stderr] Error: Failed to create bridge sockets after 5 attempts
[info] [Process] Exited, code=1, signal=null, duration=~800ms, oom=false

Version History

The app updated three times on April 16, 2026. Cowork worked fine on April 15 and broke after the April 16 updates:

| Date | App Version | Status |
|------|-------------|--------|
| Apr 15 and prior | 1.1.8629 | ✅ Working |
| Apr 16 08:15 | 1.2581.0 | ❌ Broken |
| Apr 16 08:48 | 1.2773.0 | ❌ Broken |
| Apr 16 14:16 | 1.3036.0 | ❌ Broken |

The VM bundle (rootfs.img.zst) was also updated on April 16 at ~08:39, coinciding with the first broken update.

Environment

• OS: macOS Darwin 25.4.0 (arm64)
• Current app version: 1.3036.0
• Claude CLI version: 2.1.112
• SDK installed into VM: 2.1.111
• VM bundle hash: 5680b11bcdab215cccf07e0c0bd1bd9213b0c25d
• coworkNetworkMode: gvisor

Steps to Reproduce

1. Open Claude Mac app (version 1.3036.0)
2. Start any new cowork session
3. Session immediately fails with "Claude Code process exited with code 1"

What I've Tried

• Signed out and back in — no change
• Deleted rootfs.img and sessiondata.img to force VM rebuild from rootfs.img.zst — no change
• The error is 100% reproducible on every attempt

Additional Context

The VM itself boots and connects successfully. The failure happens specifically when the Claude Code process inside the VM tries to establish bridge sockets back to the host. All infrastructure steps (vm_boot, guest_vsock_connect, sdk_install) complete successfully before the crash.