Question about common rail injector leakage (1.6Tdi CAYC engine)

Hi,
as i removed engine cover i saw that little spaces near injectors were filled with diesel. Cleaned all up, ran the engine for 15 minutes and saw where the injector leaks. (Photo)
As im a total noob in diesels and complete noob in injectors, i was wondering if someone a bit smarter could help me an tell if the leakage is somehow repairable : easy fix like trying to tighten the nut or the injector itself or some parts from it needs to be replaced?

Car:
Seat Altea XL, 1.6Tdi, 77kw,

Are you 100% sure it's the injector leaking and not valve cover (those are very common point of failures on these engines).

If it's for sure the injector, you can try tightening it while counterholding it at the same time.

Other than that, you'll probably need to visit a shop which specializes in (rebuilding) injectors.

Thanks for the reply...pretty much 100% sure its from injector. Noob question but as i tighten the nut will i also change/alter the timing of the injector?

No, it's a completely different system from Unit Injectors.