The pipe leading to this exterior faucet was apparently never secured inside the wall (contractor mistake when the wall was built):
So it pulls in and out in use, and no doubt lets rain water drip into the wall. It certainly means the grade D stucco paper behind has an unintended gap.
Accessing it from inside is hard. What would the external repair options be? What would a proper bracket look like, to secure this pipe from the outside (after caulking the heck out of the gap)?
The right thing seems almost like a floor flange:
But this flange would require pipe cutting, so it could slip over the pipe for solder, and that all seems a bit awkward also, in part because soldering might stress or melt the tar paper inside.