Life Without Walls: Circumventing Your Home Security System

by Sacha Moufarrege

I was 15, she was 14.

Our parents didn't approve at all, but we wouldn't let that stop us.  We would sneak out late at night and walk miles through a snowstorm without coats just to hug each other for a while at the halfway point.  Everything was going well until my parents figured out what was going on and decided to install a home security system.  We lived in a wealthy suburban neighborhood, and it didn't take too long to figure out that the security system was not intended to keep intruders out, but to keep me in!

At this point I had a basic knowledge of electronic circuitry and figured I'd take a shot at solving the problem at hand.  The truth is, it wasn't that I knew a whole lot about how things worked; it was that I knew how to figure it out.  I quickly set to work in learning how the new security system worked to see if there was any chance of our relationship surviving.

When armed, the alarm system was set to go off if any door or window in the house was opened.  The two basement windows were immune to this rule, but had steel bars going across them.  I figured investigating my bedroom window first would give me the most privacy.

I slid open the window and took a look at the window itself.  The window frame bore a single steel screw near the center, which looked out of place to me.  On the window sill I saw a round circular piece of plastic which just so happened to align with the metal screw in the frame of the window.

Closer inspection of the window revealed no other abnormalities, so I hypothesized that contact between the screw in the window and the plastic piece in the window sill must be the alarm system's mechanism for determining whether or not the window was open.  I further hypothesized that the screw itself was magnetic, as this seemed to be the only way it would exert any influence on the piece in the sill (which I believed to be covering up a sensor).  Holding various steel objects near the screw confirmed that there was a weak magnetism.

The interface for arming the system was located near the garage door in our kitchen.  This device contained a number pad, an LCD screen, and a light which was green when the system was disarmed and red when it was armed.  I noticed that if any doors or windows were open when the system was disarmed, the light would not be lit up at all.  I used this fact in my experiments to determine whether or not the system was seeing the window as closed, even if it was open.

I needed to obtain a suitably strong magnet for this endeavor, and just happened to have a dead 10 gig hard drive lying around.  Patiently, I pried it open using a hammer and screwdriver and removed the magnet.  After placing this magnet on the sensor in my window and checking the interface in the kitchen (this took some trial and error to get the positioning correct), I taped the magnet in place and - voilà!

I could leave any time I wanted, and my lover and I would have many joyous (albeit cold!) nights together thereafter.  One small issue which came up was that the window would have to remain only slightly open due to the space occupied by the magnet, but this wasn't too much of an issue for me.  I could always close the storm window on the outside if I got cold.

From my observations, most home security systems still make use of this mechanism to secure homes.  A magnetic field detector is used to detect the presence of a magnetized object placed inside the protected door or window, and the alarm will be set off if contact is broken.  By placing a suitably strong magnet near enough to any of these sensors, that point of entry is no longer secure.

More important than the specific workings of this system, I believe, is the process of investigation used to determine its inner workings.  This process is applicable to any situation and can be used to further one's knowledge of any subject through firsthand experience, even without much prior knowledge.

A hacker is made by his or her mindset, not by memorization of specific tools or systems.  It is my sincere opinion that in adopting effective investigatory problem solving techniques in such a manner, we can transcend our artificial limits and truly live a life without walls.

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