Most college fraternities require members to take an oath of secrecy. Most also have lots of symbols and insignia which carry greater significance. Usually, they advocate generic principles of good character.
This seems to be similar in format to Masonic societies.
[Note: I am not asking about external temptations resulting from Greek societies, like drinking and sex. **I am asking whether or not it is intrinsically harmful for a Catholic to take an oath in one of these societies.