An exploit is a method of by which a player can gain an unfair advantage within a game. What exactly constitutes "unfair" is debatable in the borderline cases but would necessarily be something not explicitly approved by the rules (provided in the manual or in-game text). Sometimes the spirit of the rules is invoked to justify labeling something as an exploit, while the more egregious exploits allow a player to have an advantage that the rules explicitly state one cannot have. A true exploit is often an oversight on the developers' part, although sometimes an exploit is more of a bug (mistake) than an oversight (not anticipating all possible cases).
Exploits in Neverwinter Nights can be reported to BioWare using the guidelines listed in the bug article. BioWare does not reveal which exploits are fixed when releasing patch notes. In keeping with this spirit, this article is geared towards helping server administrators and multiplayer module creators stop some exploits, without an explicit listing of how to exploit the game.
Character hacking[]
Player characters can be hacked to have normally unattainable stats and gear. The most common way to avoid such hacks is to run a server vault server, but even those servers can be vulnerable to exploits during character creation. Turning on the enforce legal characters setting helps to block several hacks. Those servers for which the easy fixes (and Dungeon Master policing) are not enough have turned to extensive checks in the OnClientEnter event.
PvP bypass[]
Some scripts allow players to bypass the PvP setting of an area. Scripts that server admins may want to review for this kind of oversight include
nw_s0_gate (when the caster is not under the influence of protection from evil),
the nw_s1_blt* scripts,
x1_s1_eyebray, and
x2_s2_dthmsttch.