Swordfish movie question?

Generally, no.  Passwords are largely now encrypted and so "sniffing" them with a packet sniffer is a waste of time. Wi-Fi keys are complex and modern Wi-Fi methods are hard to crack. Rainbow tables use to be able to crack XP passwords but those doors have been closed.

Back in the days where the movie was released Password Sniffers such as SSLStrip, DSNIFF & PSnuffle were quite common, and is still being used to some extend today.

A Logic Bomb is when a worm or other malicious program has a payload which triggers at a pre-defined time when particular conditions are met.

The latter above is a virus (malware) and not a sniffer per se.

All in all line in the movie this insinuates that at some stage someone worked on an app used by the DOA (In the movie) which has a backdoor programmed in.
Either he worked with the team or the team hacking the company was aware of the backdoor and exploited it.

Once in they would have embedded a virus or worm with a payload that executed at a planned time or under a specific condition.
To embed that code they might have required a password in order to execute, so they sniffed the network to obtain this password prior to dropping the logic bomb, after they had already entered the trapdoor to execute the sniff.