I have my own writer kryptonite. We call it...
Seriously, though, it can be very scary at times. Like a lot of writers, I went through an initial phase of over-description. Now, however, I tend to err on the side of under-description. I do this to such an extent that sometimes my story seems to occur in a "vacuum," with nothing but action and dialogue.
As I have talked with Tyler-Rose--who is largely responsible for bringing this problem to my attention--about "the vacuum," we have developed a new use of the verb. Thus, I vacuum settings, facial features, minor characters' personalities, and main characters' clothing... I've entirely vacuumed a knight, and a housekeeper, and probably a lot of other people and places I haven't noticed yet.
The first step to overcoming a problem like this is to accept and understand it, so now I present to you:
THE THREE STEPS OF VACUUMING YOUR STORY:
1. Exterminate all physical description of your setting. Do not describe the physical atmosphere the character is in until they actually encounter said setting. If there is a staircase leading out of the room, do not describe where it is, where it goes, what it looks like, or what it's made of until your main character actually trips over it. Ideally, it will be as if your story takes place in a white void. Or a black void. Don't even specify.
2. Turn minor characters into pudding-people. All minor characters are created equal. They are robot-like beings who exist solely for the purpose of moving the plot forward. They do not deserve personalities. They do not deserve souls. They do not even deserve faces. Therefore, give them none of these things. Envision brainless manikins wandering around with your main characters.
3. Vacuum all physical description of your main character(s). Main characters are very important, and so you should make their personalities and motivations very clear, compelling, and realistic. However, for fear of boring readers with All-Evil Description, no mention should be made of their physical appearance or what they are wearing (or what they are seeing, for that matter--see item 1). At all times there should be a possibility that your protagonist is wandering around naked, or in a pink tutu, because you have not otherwise specified their attire.
If you follow these three simple steps, you will be well on your way to a successfully vacuumed story.
Now that we know what The Vacuum is and how it happens, stay tuned to hear how I go about defeating it...