Lock bumping is a technique for easily opening most pin and tumbler type locks in under one minute given the pre-filed blank keys called bump keys and a tool to apply quick pressure such as a plastic mallet. This procedure makes lock picking absurdly easy, and takes only a few minutes training to apply the technique. You don’t even need to understand how it works, just that it does.
Some of the locks commonly considered to be impossible for lock picking are now found to be easily opened using lock bumping. Bump keys are easily obtained for most types of standard door locks, which mean entrance to such previously considered sacrosanct areas as U.S. Postal Service boxes is now a matter of a few seconds of lock picking with a lock bumping tool and bump keys.
Although most people would think that high end locks with closer milling tolerances would be safer, the reverse is true. Quality door locks move more easily in the chamber and are less likely to jam when the bump keys are used Heavier steel in the door locks, means the lock picking is less likely to damage the metal which would also cause jamming.
This technique does not work on electronic locks, rotating disk locks or magnetic locks, nor does it work on combination locks. Any lock that uses multiple pins and contains a spring is able to be bumped.
Lock bumping is definitely a scary security issue. According to security experts, they are being castigated by the U.S. government and law enforcement officials for publicizing information about lock bumping and bump keys. Law Enforcement’s stand is that if the general public did not know about the security issue it would not be a problem. Unfortunately, it appears that the information about lock bumping and bump keys has been common knowledge among lock picking organizations for at least 35 years, beginning in the 1970’s
The solution to the issue of bump keys and lock picking using lock bumping techniques appears to be to install locks which are not vulnerable to these techniques. The US Postal Service appears to have taken steps to provide locks on mailboxes which resist bump keys and lock bumping techniques.
It is prudent for U.S. consumers to educate themselves regarding the techniques and danger of the lock bumping issue and to make a security decision based on that information.