Look in the file header in Components.txt. There are various "only X" damage types, but there is no way to arbitrarily define a weapon that damages a specific type.

You could add an "only security stations" damaging weapon, then give all components with crew (CQ, Bridge, etc.) a security station ability of 1. It would simulate what you want reasonably well, and it would also aide in boarding attempts, due to removing some of those pesky security stations.
