#GRAND MASTER KEY PLUS#

#GRAND MASTER KEY PLUS#

These systems come in many forms, but plus or minus some complexity will look like this: a given lock is usually operated by its key (the “change key” or “day key”, no I don't know why), but can also be operated by a Master Key (MK) which will open any of the locks in a specific part of an organisation - department, building, floor, whatever. Plus my discovery of what I had to name “SSH Agent Reversing” (related to, but not to be confused with, “SSH Agent Forwarding”) - something so ridiculous in conception that no one sober would ever have tried it. These seem to free-up my cognitive processes from mundane constraints and tend to result in interesting discoveries such as this. Master Key systems are very expensive to install, and very expensive to change, so do not build all of your security and assurance upon them.Physical locks and keys have their place, but by themselves are insufficient for environments requiring high levels of assurance.A Mark IV Manifoil lock might be something you can leave the combination laying around for someone to see, but you can change the combination easily (and indeed should so do at intervals appropriate to the circumstances). Combining this physical advantage with fixed keying patterns is a recipe for compromised security.Physical access provides an attacker with a huge advantage.What do we learn? Well, nothing that we shouldn't have known already. It was only about ten years ago when I saw an academic paper describing something very similar that I realised that it maybe wasn't completely obvious to everyone. The first attempt at this took me about three hours, but with practice one could do it much quicker.Īt the time, this provided intellectual satisfaction and a won bet (although there was no stake other than the intellectual one sadly). You end up with a copy of the Grand Master Key.Return to step 1 and try the next “candidate pin” If it isn't the same, then you have extracted 1/6th of the GMK. If it is the same, then you probably do not have the master position you are looking for (unless it really is a single split in this lock - you will know this if you never find another split), so file it down more and repeat step 3.

Compare it with the individual key at that position. You have found “a” split in the “candidate pin”.If not, file down the “candidate pin” position and repeat step 3. If it works, you have found a split in the “candidate pin”. Except for one of the pin positions, the “candidate pin” - leave this at the highest level possible File it down to the GMK levels that you know already for “unknown” levels, use the ones for the individual lock that we have - by copying them from the individual key that we have.Ideal!Įxtracting the GMK Knowledge was a dull and repetative process best described thus: “Staff Only”, “Entrance”, “Abandon Hope All Ye Who Enter”, and so on. I had recently passed a hardware shop going out of business and bought a job lot of small thin metal signs for sticking on doors. Once the pins are lined up, or to test whether or not they are lined up, simply use a small screwdriver to turn the cylinder. You just need a small piece of metal thin enough to slide through whatever shape the slot is and thick enough to push the pins up. Or the two levels are the same, in this specific lock for this specific pin.Either it uses the other split in the pin.But in order to do so, for each of pins 1 to 6: Thus it would open all locks in all departments. The GMK simply extends this by using the “universal” levels for pins 1, 2, 3. Thus if one had access to an MK, it would already reveal to you half of the GMK. But for pins 4, 5, 6 it would use the “universal” pin levels from the Grand Master Key (GMK). The departmental Master Key would use the departments own values for pins 1, 2, 3. You'd only bother picking one of these if you didn't want anyone to know you'd opened it - otherwise a size 9 boot or door-ram is generally much quicker. Standard domestic locks, incidentally, only tend to use 5 pins. The individual locks within a department then permutated pin levels for pins 4, 5, 6. It was trivial to establish that in the specific MKS, each department was allocated a set of pin levels for pins 1, 2, 3. Lining up any of the splits in a specific pin to the correct level will allow the key to turn. For a Master Key System, you need to be able to use two or three different keys to open the same lock, so some (or all) of the pins have more than one split.

Grand master key