Santa needs the help of an experienced forensics analyst. But first, he has to make sure that you are worthy.
When unzipping the archive you get a file named X-MAS_Flag2.png, that is another ZIP file. Unzipping that again gives a logo2.png that is an image and contains the flag at the end of the file.
flag: X-MAS{W3lc0m3_t0_th3_N0rth_Pol3}