Ditto on what Mephisto has stated. I could not have put it any simpler.
Intel is as important to your empires survival as being able to defend against enemy fleets.
All I run are counter intel projects when I more than one AI without a treaty. I figure CI is best served in peace time, and what better time for an AI to gather resources from you than during peace time.
I agree that this does not sound like a bug, but is working correctly.
Again, Mephisto's discription is right on the money. IMHO.