Sudo

By default, the guest user has passwordless sudo (NOPASSWD:ALL).

The password is only generated once, on first boot. If you manually change the password and remove ~/password, it will not be regenerated on subsequent boots, the file is purely informational for the initial login.

user:
  passwordlessSudo: false

Caveats

• Requires plain: true on non-macOS guests (GHSA-2j9v-p4xj-cjw2): the guest agent's Unix socket tunneling is disabled until it can safely refuse privileged socket tunneling with passwordless sudo off.
• Only applies to cloud-init provisioned guests (QEMU/vz). Setting user.passwordlessSudo: false on WSL2 (Windows) guests returns a validation error, as WSL2 does not support this configuration as of now.
• The guest user is already a member of the adm and systemd-journal groups, which grants passive read access to /var/log/* and the full system journal independent of sudo.
• param still relies on sudo internally (param.env is read via sudo cat inside the guest), so it may not work as expected when user.passwordlessSudo: false is set. A warning is printed in this case.
• macOS: not configurable. Password-required sudo is always on (except /sbin/shutdown -h now), matching the built-in macOS guest behavior. Setting user.passwordlessSudo: true on a macOS guest returns a validation error.