My front strut boot has come loose from the upper connection. It is a low mileage car, looks like the suspension has never been touched and some of the parts have deteriorated somewhat. Not being familiar with this, I have some questions. Why is it loose? How is it fastened to the top of the strut mount? I don't see a fastener or clamp to hold it in place, is it held by the bump stop flange? Can I fix this without removing the strut? Thanks for your support.

 

The boot fits into a groove in the bumper.
you should be able to push it back up suggest a squirt of WD40 and then using something like a pencil (eraser end obviously)