A five-minute check
Check a loose cabinet handle
A moving handle does not always need replacing. Open the door and inspect its fasteners from behind. Support the handle with one hand while checking the screw heads with the other.
Match the driver
Use a screwdriver tip that fills the screw head securely. Turn it gently by hand. Stop when the handle is secure; extra force can strip a thread or damage the door surface.
If it still moves
Remove one screw while supporting the handle and inspect it for damaged threads. Keep the original part to compare with a replacement. Length and thread size must match, and the screw must not bottom out before gripping the door.
Know when to stop
If the mounting hole is enlarged or the surface is cracked, tightening harder will not repair it. Ask a competent repairer about a suitable fix for the material. These notes apply to ordinary cabinet hardware, not structural fittings or safety equipment.