/usr/lib/ is in sddm 0.14.0-4+deb9u1.
This file is owned by root:root, with mode 0o755.
..
/usr/lib/x86_64-linux-gnu/
/usr/lib/x86_64-linux-gnu/qt5/
/usr/lib/x86_64-linux-gnu/qt5/qml/
/usr/lib/x86_64-linux-gnu/qt5/qml/SddmComponents/
/usr/lib/x86_64-linux-gnu/qt5/qml/SddmComponents/Background.qml
/usr/lib/x86_64-linux-gnu/qt5/qml/SddmComponents/Button.qml
/usr/lib/x86_64-linux-gnu/qt5/qml/SddmComponents/Clock.qml
/usr/lib/x86_64-linux-gnu/qt5/qml/SddmComponents/ComboBox.qml
/usr/lib/x86_64-linux-gnu/qt5/qml/SddmComponents/ImageButton.qml
/usr/lib/x86_64-linux-gnu/qt5/qml/SddmComponents/LayoutBox.qml
/usr/lib/x86_64-linux-gnu/qt5/qml/SddmComponents/Menu.qml
/usr/lib/x86_64-linux-gnu/qt5/qml/SddmComponents/PasswordBox.qml
/usr/lib/x86_64-linux-gnu/qt5/qml/SddmComponents/PictureBox.qml
/usr/lib/x86_64-linux-gnu/qt5/qml/SddmComponents/TextBox.qml
/usr/lib/x86_64-linux-gnu/qt5/qml/SddmComponents/TextConstants.qml
/usr/lib/x86_64-linux-gnu/qt5/qml/SddmComponents/qmldir
/usr/lib/x86_64-linux-gnu/qt5/qml/SddmComponents/warning.png
/usr/lib/x86_64-linux-gnu/sddm/
/usr/lib/x86_64-linux-gnu/sddm/sddm-helper