DNS resolution fails in Claude Code Web VM even with Full network access

Environment

• Claude Code Web (remote VM)
• Network access set to "Full"

Steps to reproduce

1. Start a Claude Code Web session with "Full" network access
2. Download and run cloudflared:

curl -L --output /tmp/cloudflared https://github.com/cloudflare/cloudflared/releases/latest/download/cloudflared-linux-amd64
chmod +x /tmp/cloudflared
/tmp/cloudflared tunnel --url http://localhost:3000

Expected behavior

Cloudflared connects and provides a public trycloudflare.com URL

Actual behavior

DNS resolution fails immediately:

failed to request quick Tunnel: dial tcp: lookup api.trycloudflare.com on [::1]:53: read udp [::1]:58501->[::1]:53: read: connection refused

Analysis

The error shows DNS is trying to resolve via [::1]:53 (localhost IPv6), which refuses the connection. This suggests the VM's DNS resolver is misconfigured — it should point to a real DNS server (like 8.8.8.8 or the VM's gateway), not localhost.

This isn't a network allowlist issue since the connection is refused at the DNS level before any outbound request is made.

Impact

• Cannot use cloudflared to expose services running on the VM
• May affect other tools that rely on DNS resolution
• Occurs even with "Full" network access enabled

Workaround

None found.