It would be more idiomatic to say:
1. I've only just bought this, but it's got a leak.
2. I've only just bought this, and it's already leaking!
3. My new XYZ is leaking.
4. My new XYZ has a leak.
5. Look at that! It's brand new, and it's already leaking! I think I'll take it back to the shop and complain.
There are no doubt other possibilities!